Synthesis, Characterization, and Reactions of the Cluster Complexes

Li-Cheng Song, Guang-Ao Yu, Yang Liu, Bang-Shao Yin, Xiao-Guang Zhang, and .... Li-Cheng Song, Yu-Bin Dong, Qing-Mei Hu, Wen-Qi Gao, Dian-Shun Guo, ...
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Organometallics 1995, 14,98-106

Synthesis, Characterization, and Reactions of the Cluster Complexes Containing the Tetrahedral Cluster Core MFeCoS (M = Mo, W)and a Functionally Substituted Cyclopentadienyl Ligand. The Single Crystal X-ray Structures of T w o Double Clusters, [9'-C5€€4C (O)CH~CHBC (0)C5H4-~51[ M ( C O ) ~ F ~ ( C O ) ~ C O ( C O ) (M ~ ~ ~=- Mo, S ) I ~W)? Li-Cheng Song,*Jin-Yu Shen, and Qing-Mei Hu Department of Chemistry, Nankai University, Tianjin 300071, People's Republic of China

Xiao-Ying Huang State Key Laboratory of Structural Chemistry, Fuzhou, Fujian 350002, People$ Republic of China Received June 6, 1994@ Reactions of monoanions q5-RC5H4(C0)3M- with FeCo2(CO)&-S) gave the functional cluster complexes q5-RC5H4(C0)2MFeCo(c0)6(p3-s) (la-e, M = Mo, R = COzMe, C02Et; M = W, R = C02Me, COzEt, C(0)Me). le reacted with MeMgI, followed by hydrolysis, giving tertiary alcohol cluster q5-Me2C(OH)C5H4(CO)2~eco(cO)6 (p3-S) (2), while it reacted with NaBH4 to give the secondary alcohol cluster q5-MeCH(OH)C5H4(C0)2WFeCo(C0)6(p3-S) (3). Treatment of 3 with Et30BF4 afforded both a single cluster ether complex, q5-MeCH(OEt) C5H4 (CO)2WFeCo(CO)6(p3-S)(4), and a double cluster ether complex, (q5-C5H4MeCHOCHMeC5H4-q5)[(CO)2WFeCo(C0)6(p3-S)]2 (5). Similarly, reactions of dianions -M(C0)3[q5C5H4C(0)CH2CH2C(O)C5H4-q51(CO)3Mwith two molecules of F~CO~(CO)&Q-S) gave 1,4succinoyl(biscyclopentadieny1)-bridgeddouble cluster complex [q5-C5H4C(0)CH2CH2C(O)C5H4q5][(C0)2MFeCo(CO)6(p3-S)]2 (621,M = Mo, 6b,M = W).These complexes could be further reduced by NaBH4 to give dihydroxyl derivatives [q5-C5H4CH(OH)CH2CH2CH(OH)C5H4q5][(CO)zMFeCo(CO)6Cu3-s)]2 (7a, M = Mo; 7b, M = W). Treatment of 7a and 7b with Et3OBF4 afforded two unexpected double clusters containing a biscyclopentadienyl-substituted tetrahydrofuran bridge ( a - q 5 - C 5 H 4 - C ~ H ~ O - C 5 H ~ - q 5 - a ' ) [ ( ~ ~ ) 2 (8a, M FM e ~=oMo, ~~~~~~~-~]~ 8b,M = W). X-ray structures of 6a and 6b have been determined. Crystal data for 6a: triclinic, space group P-1 (No. 2), a = 7.602(3) b = 8.112(4) c = 16.208(3) a = 97.58(3)", p = 94.05(2)", y = 109.50(3)", V = 927(1) 2 = 1. Crystal data for 6b: monoclinic, space group C2/c (No. E),a = 26.448(7) b = 9.660(4) c = 14.687(5) p = 100.72(2)", V = 3687(4) A3, 2 = 4.

A,

A

A,

Introduction In recent years transition metal cluster complexes have been receiving considerable attention, largely because of their potential applications in catalysis and because of the novelty and versatility of their reactions and s t r u ~ t u r e s . l -Among ~~ these, however, there are very few cluster complexes containing a functionally T Dedicated to Professor Dietmar Seyferth, on the occasion of his 65th birthday and in recognition of his outstanding contributions to organometallic chemistry. Abstract published in Advance ACS Abstracts, November 1,1994. (1)Vahrenkamp, H. In Transition Metal Chemistry-Current Problems of General, Biological and Catalytic Relevance; Muller, A., Diemann, E., Eds.; Verlag Chemie, 1981;p 35. (2)Cotton, F. A.; Chisholm, M. H. Chem. Eng. News 1982,60,40. (3)Roberts, D. A.; Geofioy, G. L. In Comprehensive Organometallic Chemistry; Wilkinson, G., Stone, F. G. A., Abel, E. W., Eds.; Pergamon Press: Oxford, England, 1982;Vol. 6,pp 763-877. (4)Muetterties, E.L.; Krause, M. J . Angew. Chem., Znt. Ed. Engl. 1983,22,135. ( 5 ) Stone, F. G. A. Angew. Chem., Int. Ed. Engl. 1984,23,89. (6)Fischer, K;Miiller, M.; Vahrenkamp, H. Angew. Chem., Int. Ed. Engl. 1984,23,140. (7) Mlekuz, M.; Bougeard, P.; Sayer, B. G.; Faggiani, R.; Lock, C. J. L.; McGlinchey, M. J.; Jaouen, G.Organometallics 1985,4,2046. (8)Chen, W.; Goh, L. Y . ;Mak, T. C. W. Organometallics 1986,5, 1997. @

d3,

A,

A,

A,

substituted cyclopentadienyl ligand attached to group 6 metals,14 although the corresponding m o n ~ - , di~~J~ (9)Li, p.; Curtis, M. D. Inorg. Chem. 1990,29,1242. (10)Chetcuti, M. J.;Gordon, J. C.; Fanwick, P. E. Inorg. Chem. 1990, 29,3781. (11)(a) Adams, R. D.; Pompeo, M. P. Organometallics 1992, 11, 1460. (b) Adams, R. D.; Belinski, J. A. Organometallics 1992,11,2488. (c) Adams, R. D.; Cortopass; J. E.; Falloon, S. B. Organometallics 1992, 11, 3794. (12)(a) Seyferth, D.; Song, L.-C.; Henderson, R. S. J. Am. Chem. SOC.1981,103,5103. (b) Seyferth, D.;Henderson, R. S.; Song, L.-C. Organometallics 1982,1, 125. (c) Cowie, M.; DeKock, R. L., Wagenmaker, T. R.; Seyferth, D.; Henderson, R. S.; Gallagher, M. K. Organometallics 1989,8,119.(d) Seyferth, D.; Womack, G. B.; Archer, C. M.; Dewan, J. C. Organometallics 1989,8,430. (e) Seyferth, D.; Womack, G. B.; Archer, C. M.; Fackler, J. P., Jr.; Marler, D. 0. Organometallics 1989,8,443. (13)(a) Song, L.-C., Kadiata, M.; Wang, J.-T.; Wang, R.-J.; Wang, H.-G. J. Organomet. Chem. 1988,340,239. (b) Song, L.-C., Kadiata, M.; Wang, J.-T.; Wang, R.-J.; Wang, H.-G. J.Organomet. Chem. 1990, 391, 387. (c) Song, L.-C.; Hu, Q.-M. J. Organomet. Chem. 1991,414, 219. (d) Song, L.-C.; Hu, Q.-M.; Zhang, L.-Y.; Wang, H.; Zhou, 2.-Y.; Liu, L. J. Organomet. Chem. 1991,412,C19. (14)Song, L.-C.; Shen, J.-Y.; Hu, Q.-M.; Wang, R.-J.; Wang, H.-G. Organometallics 1993,12,408. (15)Macomber, D. W.; Hart, W. P.; Rausch, M. D. Advances in Organometallic Chemistry, Academic Press., Inc.: New York, 1982; VOl. 21, p 1.

0276-733319512314-0098$09.00/0 0 1995 American Chemical Society

Cluster Complexes Containing MFeCoS

Organometallics, Vol. 14, No. 1, 1995 99

Scheme 1

I Clusters

M R

la-e

la lb Mo Mo COzMe C a E t

IC

W CQMe

Id W

le

w

CGEt C(0)Me

and linear trinuclear18 complexes have been wellstudied. In this article, we wish to report the synthesis, characterization, and some of the interesting reactions of this novel type of cluster complex, as well as the X-ray structure analyses for two such compounds. I5-l7

Results and Discussion Part 1. The Chemistry Starting from the Monoanions q5-RC5&(C0)&I-(I). Preparations of lae. Functionally substituted cyclopentadienyl tricarbonyl group 6 metal anions q5-RC5H4(C0)3M-(R = MeCO, MeOzC, etc.) (I) have proved to be important in the synthesis of organometallic and metal cluster complexes containing the structural unit q5-RC5H4 (CO)zM.14-18This is because the commonly used electrophilic substitution of the cyclopentadienyl ring of their parent compounds could not be applied to prepare this type of complex, due to their inherent lack of aromatic character andlor their decomposition under substitution conditions involved.14J5 Now we have found an additional use of the monoanions I in the synthesis of the tetrahedral MFeCoS (M = Mo, W) cluster complexes. For instance, complexes la-e can be prepared by their reaction with the cluster complex FeCoz(CO)g@s-S)in THF at reflux in 41-69% yield, as shown in Scheme 1. Actually, this is an isolobal displacement consequencelg of Co(C0)3(dgML3)in FeCo2(CO)g@&) by 115-RC5H4(C0)~M(d5ML5) generated in situ from the anions I. However, it is worth noting that our initial attempts to obtain cluster l e failed when an electrophilic aromatic substitution reaction of the parent compound CpWFeCo (CO)8@3-S) with acetyl chloride in the presence of AlCl3 in CH2C12 at room temperature was tried. From the reaction mixture only 48% of the parent cluster was recovered, showing the inherent lack of aromaticity and the severe decomposition of the parent cluster under the Friedel-Crafts conditions. Reactions of 1 and Formation of 2-5. Although reactions of the functional group of a cyclopentadienyl (16)(a) Song, L.-C.; Dong, Q.; Hu,Q.-M. Acta. Chim. Sin. 1991,49, 1129. (b) Song, L.-C.; Dong, Q.; Hu, Q.-M. Youji Huaxue 1992,12,35. (c) Song, L.-C.; Shen, J.-Y.; Hu, Q.-M. Sci. China (series B) 1993,36, 1281. (17)(a) Song, L.-C.; Shen, J.-Y. Chem. J . Chin. Uniu. 1992,13,1227. (b) Edelmann, F.;Tofke, S.; Behrens, U. J . Organomet. Chem. 1986, 309,87. (c) Avey, A.; Tenhaeff, S. C.; Weakley, T. J. R.; Tyler, D. R. Organometallics 1991,10, 3607. (18)(a) Song, L.-C.; Dong, Q.; Hu, Q.-M. Acta Chim. Sin. 1992,50, 193. (b) Song, L.-C.; Yang, H.; Dong, Q.; Hu, Q.-M. J . Organomet. Chem. 1991,414,137.(c) Medina, R. M.; Masaguer, J. R.; Moran, M.; Losada, J. Inorg. Chim. Acta 1988,146,115. (19)(a) Hoffmann, R. Angew. Chem., Znt. Ed. Engl. 1982,21,711. (b) Vahrenkamp, H. Comments Znorg. C h m . 1985, 4, 253. (c) Kaganovich, V. S.; Slovokhotov, Yu.L.; Mironov, A. V.; Struchkov, Yu. T.; Rybinskaya, M. I. J . Organomet. Chem. 1989,372,339.

ring in mononuclear transition metal complexes, such as ferrocene derivativesz0 and group 6 monometallic compounds,21have been extensively studied, the investigations of this kind of reaction involved in dinuclear compounds and especially in cluster systems are relatively few.15J6cIn principle, the cluster core in cluster complexes may influence the reactivity of the functional group on the cyclopentadienyl ring and also could be destroyed under the reaction conditions used. Rausch reported that (q5-carbomethoxycyclopentadienyl)tricarbonylmethyltungsten was saponified with potassium hydroxide in aqueous methanol at 25 "C to give, after acidification, the corresponding carboxylic acid in 82% yield.21a However, treatment of cluster ICin methanol with aqueous potassium hydroxide, followed by acidification, did not give the expected carboxylic acid. In fact, when potassium hydroxide was added to the solution of IC,a color change from brown-red to brownblack occurred immediately, presumably due to the decomposition of cluster ICunder the basic conditions of saponfication. In contrast to the different hydrolysis behavior of the carbomethoxy group as mentioned above, the acetyl group in cluster l e showed chemical behavior similar to that of some mononuclear compoundszlb,ctoward Grignard reagents and NaBH4. For instance, l e reacted with MeMgI in ether at room temperature, after hydrolysis of the addition intermediate, to give tertiary alcohol 2 in 39%yield as shown in Scheme 2. Also as shown in Scheme 2, l e could be reduced by NaBH4 in MeOH at room temperature to give secondary alcohol 3 in 55% yield. It is interesting that 3 could further react with triethyloxyonium tetrafluoroborate salt Et30BF4, as in the case of an organic in CHZClz at room temperature to give the expected alkylation product 4 in 29%yield. However, the reaction also gave an unexpected product, 5, formally viewed as derived by loss of one molecule of water from two molecules of 3, in 31% yield, as shown in Scheme 2. The mechanisms for ether formation from alcohols under acidic conditions are well-known in organic and organometallic chemistry. So, as in the case of organic alcohols,22the alkylation product 4 would be produced through a pathway which involves the attack of the Et+ cation generated from dissociation of the oxonium salt a t the oxygen atom of hydroxy group of the cluster 3 to form the intermediate ml, followed by loss of HBF4. H

However, the carbon atom attached to the Cp ring of the intermediate ml might be possibly further attacked (20)Bublitz, D. E.;Rinehart, K. L., J r . In Organic Reactions; Dauben, W. G., Ed.; John Wiley & Sons, Inc.: New York, 1969 Vol. 17,pp 1-154. (21)(a) Macomber, D. W., Rausch, M. D. J . Organomet. Chem. 1983, 258,331. (b) Rausch, M. D.; Mintz, E. A., Macomber, D. W. J . Org. Chem. 1980,45,689. (c) Hart, W. P.; Rausch, M. D. J . Organomet. Chem. 1988,355,455. (22)Diem, M. J.; Burow, D. F.; Fry,J. L. J . Org. Chem. 1977,42, 1801.

100 Organometallics, Vol. 14, No. 1, 1995

Song et al.

Scheme 2 OH 0

@ & M 2e W

iC0)a

OEt

6a M = M o , 6b M = W

by the nucleophilic oxygen atom of the hydroxyl group of 3 with loss of one molecule of EtOH to generate another intermediate, m2. Then, 5 would be finally afforded from m2 by loss of HBF4. Interestingly, to our knowledge, this reaction is the first example so far for producing a symmetrical double cluster ether such as 5 by the action of a trialkyloxonium salt upon the corresponding alcohol. However, the detailed mechanism for this reaction still needs further study. Characterization of la-e and 2-5. Compounds la-e are solid colored from brown-red to black, while 2-5 are red viscous oils. They were all fully characterized by elemental analysis and IR, lH NMR and MS spectroscopies. In their IR spectra all showed terminal carbonyl absorption bandsz3in the range of 2082-1901 cm-l, and bridging carbonylsz3 might exist for la,c,e and 3-5, evidenced by one absorption band present between 1860 and 1890 cm-l. The IR spectra of la-e also showed corresponding carbonyl absorption bands of ester at around 1720 cm-l and acetyl at 1685 cm-’, while the IR spectra of 2 and 3 showed the hydroxyl group at around 3427 cm-l. As we know, lH NMR spectra of a monosubstituted cyclopentadienyl ring in transition metal compounds vary greatly in complexity, such as a single resonance, an A2Bz or AzBB‘ pattern or a multiplet pattern, all depending on the nature of the substituent.21 For the lH NMR spectra of la-e, the four protons on the cyclopentadienyl ring exhibited an AzBB’ pattern. The AzBB’ pattern consisted of two closely spaced quartets of relative intensity 1H upfield from 5.40 ppm and a triplet (or a quartet for le) of relative intensity 2H downfield from 6.04ppm. The two upfield quartets had been assigned to the H3 and H4 protons remote from the electron-withdrawing substitu(23)Collman, J. P.;Hegedus, L. S.; Norton, J. R.; Finke, R. G. Principles and Applications of Organotransition Metal Chemistry; 2nd ed.; California University Science Books: Mill Valley, 1987.

ent, since they were deshielded to a less extent than H2and H5 close to the substituent. We believe that the AzBB’ pattern was caused by the chirality of the tetrahedral cluster core MFeCoS. It is the chiral core that makes H3and H4 protons diastereotopic. However, a t present, we do not fully understand why H3 and H4 are diastereotopic whereas H2and H5are not. Perhaps, this is due to H3 and H4 being closer than H2 and H5 to the chiral cluster core. In contrast to the lH NMR spectra of la-e, the ‘H NMR spectra of the cyclopentadienyl protons of 2-5 showed more complicated patterns. Obviously, this can be attributed (except for cluster 2) t o the influences from both the chiral cluster core and the chiral a-carbon atom attached to cyclopentadienyl ring. The mass spectra of la,b,d,e and 4 showed their parent ion peaks, the fragment ion peaks of successive loss of a given number of CO from parent ion, the respective cluster core peaks, and so on. Although no parent ion peaks appeared in the mass spectra of IC,2, and 3, the peaks of corresponding fragment ions similar to those mentioned above existed. Part 2. The Chemistry Generated from the Bridging Dianions ( ~ I ~ - C ~ H ~ C ( O ) C H Z C H Z C ( O ) ~ ~ H ~ ~ , I ~ ) ( C O ) ~(1M 1).~ ~Preparations of 6a,b. Reactions of 1,4-succinoylbis(cyclopentadienylsodium) with Mo(COh in THF or with W(CO)6 in diglyme at reflux for several hours gave dianions 11,which could react in situ with two molecules of FeCoz(CO)&3-S), through d5ML5/ dgML3 double isolobal displacement, to afford 6a and 6b in 31% and 43% yields, respectively, as shown in Scheme 3. This type of double isolobal displacment, t o our knowledge, is unprecedented. Reactions of 6a,b and Formation of 7a,b and 8a,b. The functionality in double cluster complexes 6a and 6b, just like those in the above single cluster complexes, could be transformed into other functional-

8r

M = M o . 8b M = W

ities. Thus, 6a and 6b reacted with NaBH4 in CH30H at room temperature, giving dihydroxy derivatives 7a and 7b in 31%and 23%yields, as shown in Scheme 4. Interestingly, the 1,4-dihydroxylbutylenegroup in 7a and 7b,under the action of Et30BF4 in CH2C12 at reflux, was converted into an a,a'-disubstituted tetrahydrofuran ring affording 8a and 8b in 90% and 89% yields, as shown in Scheme 4. TLC showed no formation of 8a and 8b below 0 "C after 2 h, while 8a and 8b were produced at 18 "C after 2 h in 86% and 39% yields, respectively. 8a and 8b might also be produced by use of HBF4 or HC1 instead of Et30BF4, in spite of the lower yields. For example, in the case of using HBF4 the reaction at reflux for 2 h gave 8a in 58% yield whereas the reaction, when HC1 was used, at reflux for 9 h gave 8b only in 12% yield. The mechanism for producing complexes 8a and 8b under these conditions is similar to that for formation of 4 and 5 described above. The reaction may involve initial attack of electrophilic E(representing H+ or Et+ generated by dissociation from HC1, HBF4 and Et30BF4) a t the oxygen atom of one hydroxy group of 7a or 7b to form the intermediate m,which in turn loses one molecule of water or ethanol E

*OH

OH

H

p;.

m,

by the intramolecular attack of the oxygen atom of another hydroxyl group at the carbon atom attached to

EOH moiety to give the protonated species a.Finally the a loses one proton to give 8a or 8b. Although the dehydration from diols leading to a substituted tetrahydrofuran derivatives by the action of proton acid or the others is a known the process occurred by the action of Et30BF4 to form a,a'-bis(cyclopentadieny1)tetrahydrofuran bridged double cluster complexes 8a and 8b is unprecedented in literature. Characterization of 6a,b,7a,b,and 8a,b. Except for 8a, which is a brown viscous oil, 6a,b,7a,b, and 8b are brown solids and have been characterized by CiH analysis and IR and lH NMR spectroscopies. In their IR spectra, there exist four absorption bands, in which three bands in the range of 2077-1967 cm-l are assigned t o terminal carbonyls and one band around 1885 cm-' is assigned to a bridging carbonyl.23 Besides these absorptions for carbonyls attached to metals, there is a moderately strong absorption band around 1682 cm-I for the ketonic carbonyl of 6a,b,while there is a broad absorption band around 3400 cm-l for the hydroxyl group of 7a,b. The IH NMR spectra of cyclopentadienyl protons for double clusters 6a,b,7a,b,and 8a,b are also as complicated as those for clusters 1-5 mentioned above. This is reasonable because these double clusters all contain the chiral tetrahedral cluster core MFeCoS and 7a,b and 8a,b contain the chiral a-carbon atom attached to the cyclopentadienyl ring as well. For 6a,b the lH NMR spectra of each cyclopentadienyl protons show an A2BB pattern, of which the two upfield sets of quartets are assigned to H3 and H4 remote from succinoyl bridge and the downfield triplet or multiplet is assigned to H2and H5 close to the bridge, due to the electron-withdrawing effect of the succinoyl group. However, for 7a,b the 'H NMR spectra show two multiplets, while for 8a,b there is one multiplet. Based on the same reason, for 7a,bthe upfield multiplet should be assigned to H3 and H4, while the downfield multiplet is assigned to H2 and H5. The chemical shifts of the hydroxyl group for 7a,b were established by the D/H exchange method, which included adding DzO to the lH NMR tube and redetermination of the lH NMR of 7a,b, showing complete disappearance of the peak for the hydroxyl group. X-ray Structure Analysis. In order to confirm the structures of 6a and 6b, a study of their X-ray diffrac(24) Jacobus, J. J. Org. Chem. 1973,38,403.

102 Organometallics, Vol. 14, No. 1, 1995

Song et al.

Table 1. Fractional Coordinates and Equivalent Isotropic Thermal Parameters for 6a atom

X

Y

Z

B(eq), A’

Mo(1) Co(1) Fe(1) S(1) O(1) C(1) O(2) C(2) o(3) C(3) o(4) C(4)

0.4244( 1) 0.5758(1) 0.2791(1) 0.5520(3) -0.0089(9) 0.155(1) 0.332( 1) 0.370(1) 0.004(1) 0.109(1) 0.328( 1) 0.313( 1) 0.049(1) 0.135(1) 0.923(1) 0.789( 1) 0.721(1) 0.668( 1) 0.387( 1) 0.458( 1) 0.398(1) 0.409(1) 0.585(1) 0.686(1) 0.575(1) 0.243(1) 0.251(1) 0.071(1)

0.19938(9) 0.4178(1) 0.1434(1) 0.1417(3) 0.026(1) 0.091(1) 0.540(1) 0.419(1) 0.324(1) 0.251(1) 0.152(1) 0.150(1) -0.233(1) -0.088(1) 0.611(1) 0.538(1) 0.456(1) 0.443(1) 0.679(1) 0.573(1) 0.135(1) -0.018(1) 0.026(1) 0.206(1) 0.275(1) 0.151(1) 0.2917(8) -0.016(1)

0.79774(4) 0.68230(7) 0.62866(7) 0.6749(1) 0.7703(5) 0.7688(6) 0.8523(5) 0.8252(6) 0.6297(5) 0.6302(5) 0.4535(4) 0.5230(6) 0.5975(6) 0.6092(6) 0.7955(5) 0.7518(7) 0.5205(4) 0.5832(6) 0.6852(5) 0.6843(5) 0.9306(5) 0.8810(5) 0.8528(6) 0.8858(6) 0.9344(5) 0.9765(5) 1.0156(4) 0.9732(5)

2.39(2) 3.05(4) 2.81(4) 3.05(7) 6.6(3) 4.0(4) 7.7(4) 4.3(4) 6.7(4) 3.5(3) 6.2(3) 3.9(3) 8.0(4) 4.5(4) 6.7(3) 4.7(4) 5.6(3) 3.6(3) 6.3(3) 3.8(3) 2.8(3) 3.4(3) 3.5(3) 4.0(4) 3.2(3) 3.1(3) 5.3(3) 3.0(3)

o(5)

C(5) O(6) C(6) o(7) C(7) O(8) C(8) C(11) C(12) C(13) C(14) C(15) C(16) o(9) C(17)

Table 2. Fractional Coordinates and Equivalent Isotropic Thermal Parameters for 6b atom

X

Y

Z

B(ed, .A2

0.62278(2) 0.65727(7) 0.62502(8) 0.6928( 1) 0.5946(5\ . ~. 0.6060i5j 0.5087(4) 0.5520(6) 0.7125(4) 0.6904(6) 0.7070(6) 0.6881(6) 0.5579(5) 0.5958(6) 0.5234(5) 0.5625(7) 0.6802(5) 0.6579(7) 0.6138(6) 0.6177(7) b.6064(6) 0.6600(6) 0.6785(6) 0.6384(6) 0.5949(6) 0.5712(6) 0.5914(5) 0.5147(5)

0.2712l(5) 0.2129(2) 0.0078(2) 0.1352(3) 0.080(1\ .~~ 0.145ii j 0.242( 1) 0.245(1) 0.470( 1) 0.370(2) 0.060( 1) 0.113(2) 0.270(1) 0.244(2) -0.040( 1) -0.019(2) -0.198( 1) -0.1 16(2) -0.193( 1) -0.1 12(2) 0.434( 1) 0.407(2) 0.457(2) 0.509(2) 0.498( 1) 0.414( 1) 0.391(1) 0.425(2)

0.01240(4) 0.1975(1) 0.0925(1) 0.0845(3) -0.1606f8) -0.093(1 j ’ 0.034( 1) 0.030( 1) 0.2517(8) 0.228( 1) 0.3629(9) 0.297( 1) 0.2466(9) 0.226( 1) 0.139(1) 0.119(1) 0.217(1) 0.171(1) -0.058( 1) 0.002( 1) -0.102(1) -0.084( 1) 0.003( 1) 0.043( 1) -0.022( 1) -0.196( 1) -0.2643(8) -0.201(1)

1.88(2) 2.41(8) 2.56(9) 2.4(1) 4.5(6) 2.3i6j 5.2(6) 3.1(7) 4.7(6) 3.3(7) 6.6(8) 3.6(8) 5.0(6) 3.4(7) 5.8(7) 3.5(7) 6.1(7) 3.5(8) 6.8(8) 3.5(7) 3.1(7) 4.0(8) 3.2(7) 3.1(7) 3.1(6) 2.9(7) 4.5(6) 2.9(7)

~

~~~~

tion was undertaken. The final fractional coordinates with equivalent isotropic thermal parameters are listed in Tables 1and 2. Tables 3 and 4 list the selected bond lengths and bond angles. The perspective views of 6a and 6b are presented in Figures 1 and 2, respectively. As seen from Figure 1, the molecule 6a consists of two identical tetrahedral subclusters, FeMoCoS, carrying eight carbonyls and one 1,4-succinoyl-bridgedbiscyclopentadienyl ligand. The two subclusters are connected through Mo atoms to two ~+cyclopentadienyl rings in a trans fashion. Among the eight carbonyls attached to the metals, two carbonyls attached t o the

07

Figure 1. ORTEP diagram of 6a showing 30% probability thermal ellipsoids.

04

Figure 2. ORTEP diagram of 6b showing 30% probability thermal ellipsoids. Table 3. Selected Bond Lengths Angles (deg) for 6a

(A) and

atoms

distance

atom

distance

Mo(1)-C( 1) Mo(l)-C(2) Mo(l)-C(ll) Mo(1)-S(1) Mo( l)-Co( 1) Mo( 1)-Fe( 1)

1.937(9) 1.96(1) 2.288(8) 2.335(2) 2.790(2) 2.801(1)

Fe(1)-S(1) 0(1)-C(1) Co( 1)-5(1) Co( 1)-Fe( 1) C(ll)-C(16) C(16)-O(9)

2.161(2) 1.18( 1) 2.172(3) 2.580(2) 1.47(1) 1.21(1)

atoms

angle

C( l)-Mo(l)-C(2) C( 1)-Mo( 1)-Fe( 1) C(2)-Mo( 1)-CO( 1) S(1)-Co(1)-Fe(1) S(l)-Co(l)-Mo( 1) Fe( 1)-Co( 1)-Mo( 1) S( 1)-Fe( 1)-Co( 1)

84.1(4) 62.1(3) 72.5(3) 53.25(7) 54.45(7) 62.74(5) 53.66(7)

atoms S(1)-Fe(1)-Mo(1) Co(1)-Fe(1)-Mo(1) Fe(1)-S(1)-Co(1) Fe(1)-S(1)-Mo(1) Co(1)-S(1)-Mo(1) S(1)-Mo(1)-Co(1) S(1)-Mo(1)-Fe(1)

angle 54.31(6) 62.29(5) 73.09(8) 76.96(7) 76.38(8) 49.18(6) 48.72(6)

Table 4. Selected Bond Lengths (A) and Angles (deg) for 6b atoms

distance

atoms

distance

W(l)-C(2) W(l)-C(1) W(l)-C(ll) W( l)-S(1) W( 1)-Co( 1) W(1)-Fe(1)

1.95(1) 1.96(1) 2.28( 1) 2.355(4) 2.761(2) 2.799(2)

Fe(1)-S(1) 0(1)-C(1) Co( 1)-5(1) Co( 1)-Fe( 1) C(l1)-C(16) C(16)-0(17)

2.194(4) 1.16(2) 2.187(4) 2.558(3) 1.54(2) 1.24(2)

atoms

angle

atoms

angle

C(2)-W(l)-C(l) C(2)-W(l)-Fe(l) C( 1)-W( 1)-Fe(1) C(4)-Co(l)-W(l) S(l)-Co(l)-Fe(l) S(l)-Co(l)-W(l) S(l)-Fe(l)-Co(l)

86.8(6) 76.8(4) 75.6(4) 156.9(5) 54.4(1) 55.4(1) 54.1(1)

S(1)-Fe(1)-W(1) Co(1)-Fe(1)-W(1) Co( 1)-S( 1)-Fe( 1) Co(1)-S(1)-W(1) Fe(1)-S(1)-W(1) S(1)-W(1)-Co(1) S(1)-W(1)-Fe(1)

54.7(1) 61.85(7) 71.4( 1) 74.8(1) 75.9(1) 49.8(1) 49.5(1)

Mo atom are semibridging and the other terminal. The existence of both terminal and semibridging CO’s confirmed by X-ray diffraction is consistent with the IR spectrum of 6a described above. For semibridging carbonyls Curtis’s definition25is 0.1 Ia = (&-cll)/& 5 0.6. Since d2 = Fe(1) -C(l) = 2.554 A and dl = Mo(l)-C(l) = 1.937 A, a for C(1)0(1) = 0.32; since d2 =

Organometallics, Vol. 14,No. 1, 1995 103

Cluster Complexes Containing MFeCoS

Table 5. Comparison of the Bond Lengths (A) of the Cluster Core in 6a and 6b with Those of Two Single Clusters clusters"

Mo-Fe

Mo-CO

Fe-Co

Mo-S

CpMoFeCo(C0)7L@3-S) 6a

2.793(2) 2.801(1)

2.750(2) 2.790(2)

2.568(2) 2.580(2)

2.363(3) 2.335(2)

Fe-S

co-s ~

a

2.182(3) 2.161(2)

2.170(3) 2.172(3)

clusters

W-Fe

w-co

Fe-Co

w-s

Fe-S

co-s

CpWFeCo(CO),L@3-S) 6b

2.792(2) 2.799(2)

2.730(2) 2.761(2)

2.574(2) 2.558(3)

2.348(3) 2.355(4)

2.187(3) 2.194(4)

2.179(4) 2.187(4)

L = MePrPhP.

Co(1) -C(2) = 2.89 A and dl = Mo(l)-C(2) = 1.96 8,a and (-)-CpWFeCo(C0)7(MePrPhP)@&3), as shown in for C(2)0(2) = 0.47. So, they all fall into the a value Table 5. range for semibridging carbonyls. Since the angle of From Table 5 it can be seen that all the corresponding Fe(l)Mo(l)C(l)is 62.1", the C(1)0(1) is bridged across bond lengths are basically the same, except that the the Mo(l)Fe(l)bond while C(2)0(2) is bridged across Mo-Co bond of 6a and the W-Co bond of 6b are slightly the Co(l)Mo(l) bond due to the angle (72.5") Co(1)Molonger than those of corresponding bond in (+)-CpMoFeCo(C0)7(MePrPhP)@3-S)and (-)-CpWFeCo(CO)7(1)C(2). The cyclopentadienyl ring is tilted to the triangular plane Fe(1)-Co(1)-S(1) and gives a dihedral (MePrPhP)@s-S),respectively. angle of 48.12". The Mo atom-Cp ring centroid disIt should be mentioned that the crystal molecule of tance is 2.001 A. Since the dihedral angle between the 6a is that of an achiral molecule containing a symmetric cyclopentadienyl ring and the plane C(16)-0(9)-C(17) center, which is actually one of three possible optical is rather small (4.76'1, the n-system of half of the isomers, namely the meso form; the crystal molecule of succinoyl bridge C(16)0(9)C(17) would be quite well 6b is that of a chiral molecule containing a 2-fold conjugated with the Cp ring n-system and thus the bond symmetric axis, which is the R form of three possible length of C(ll)-C(16) (1.47 A) becomes much shorter optical isomers. However, no matter what they are, the than a normal C-C single bond. 'H NMR spectra of the cyclopentadienyl protons of 6a Also, 6b as seen from Figure 2, consists of two and 6b should show an A2BB' pattern as mentioned identical tetrahedral subclusters, FeCoWS, carrying above. This is because they all contain a chiral tetraeight carbonyls and one 1,4-succinoyl-bridgedbiscyclohedral subcluster, MFeCoS, which would make the two pentadienyl ligand. Just like 6a, two carbonyls, i.e., protons H3 and H4 of the cyclopentadienyl diasteC(1)0(1) and C(2)0(2) attached to the W atom, are reotopic. semibridging and the other six terminal. This is in good agreement with the IR spectrum of 6b. However, since Experimental Section the angles Fe(l)W(l)C(l)and Fe(l)W(l)C(2)are 75.6All reactions were carried out under prepurified nitrogen (4)" and 76.8 (4)", respectively, these two carbonyls atmosphere using standard Schlenk or vacuum line techappear to be both bridged across the Fe(l)-W(l) bond. niques. THF and diglyme were distilled from sodiumFor C(1)0(1), a = 0.53 [since W(l)-C(l) = 1.96(1) A, benzophenone ketyl under nitrogen. Column chromatography Fe(1) -C(l) = 2.99 (1)81. For C(2)0(2),a = 0.55 [since and TLC were carried out by using silica gel of 300-400 mesh W(l)-C(2) = 1.95(1) Fe(1) -C(2) = 3.03(1) The and silica gel G (10-40 pm), respectively. MO(CO)~, W(CO)6, cyclopentadienyl ring of 6b is tilted to the triangular and COZ(CO)S were purchased from Strem Chemicals Inc. Et3plane Fe(1)-Co(1)-S(1) and gives a dihedral angle of OBF4,27 FeCoz(C0)9S,lZcRCsH4Na (R = MeCO, MeOZC, EtOzC),2s,zgand [ N ~ C ~ & C ( O ) C Hwere ~ ] Z ~prepared ~ according 46.87", a value slightly less than that in the case of 6a. to literature methods. IR spectra were recorded on a NICOThe distance W atom-Cp-ring centroid (1.998 A) is LET FT-IR 5DX infrared spectrophotometer; 'H NMR spectra almost the same as the corresponding one in 6a. were recorded on a JEOL FX 9OQ N M R spectrometer. C/H However, the n-system of half of the succinoyl bridge, analyses and MS determinations were performed by a 240 C C(16)-0(17)-C(18), is not well conjugated with the analyzer and HP 5988 A spectrometer, respectively. Melting cyclopentadienyl ring n-system, since the dihedral angle points were determined on a Yanaco micromelting point between the cyclopentadienyl plane and the plane apparatus MP-500. C(16)-0(17)-C(18) is quite larger (15.32"). This can Preparationsof la-e. A 100 mL two-necked flask fitted be reflected by the fact that the bond length of C(l1)with a magnetic bar, a rubber septum, and reflux condenser C(l6) (1.54 A) is actually the same as the value of a topped with a nitrogen inlet tube was charged with 528 mg normal C-C single bond. (2.0mmol) of Mo (CO)6, 292 mg (2.0 mmol) of MeOzCC5Haa, and 20 mL of THF. The mixture was refluxed for 15 h. Upon So far, no double cluster complexes containing tetracooling to room temperature, 458 mg (1.0 mmol) of FeCoz(C0)ghedral subcluster core MFeCoS are reported, although (p8-S) was added and the mixture stirred at reflux for an a few such single cluster complexes have appeared in additional 1h. Solvent was removed under reduced pressure the literature.26 The related bond lengths for the cluster and the residue extracted with CHzClz. The extracts were core of 6a and 6b are compared with those of two known subjected to chromatographic separation on a silica gel column. single clusters26d(+)-CpMoFeCo(CO~~(MePrPhP~~~-S~ After elution with 1:l petroleum ether/CHzCl2, followed by

A,

19, 2096.

evaporation of solvents, 240 mg (41%) of la as a black solid was obtained. The sample for analysis was further purified

(26)(a) Richter, F.; Vahrenkamp, H. Angew. Chem. Znt. Ed. Engl. 1978,17,863.(b) Richter, F.; Vahrenkamp, H. Angew. Chem. Int. Ed. Engl. 1978,17,864. (c) Richter, F.;Vahrenkamp, H. Organometallics 1982,I , 756. (d) Richter, F.; Vahrenkamp, H. Chem. Ber. 1982,115, Zhao, Z.-Y.;Yin, Y.-Q.;Huang, L.-R. Chinese Sci. 3243. (e) Yang, H.; Bull. 1992,37,1804. (0 Sun, W.-H.; Yang, S.-Y.;Wang, H.-Q.;Zhou, Q.-F.;Yu, K.-B. J . Organomet. Chem. 1994,465,263.

(27)Meerwein, H.Org. Synth. 1986,46,113. (28)Rogers, R. D.; Atwood, J. L., Rausch, M. D.; Macomber, D. W.; Hart, W. P. J. Organomet. Chem. 1982,238,79. (29)Hart, W.P.,Dong, S.; Rausch, M. D. J.Organomet. Chem. 1986, 282,111. (30)Bittenvolf, T. E. J. Organomet. Chem. 1990,386,9.

(25)Curtis, M. D.; Han, K. R.; Butler, W. M. Inorg. Chem. 1980,

104 Organometallics, Vol. 14,No. 1, 1995 by recrystallization from 1:lpetroleum etherlCHzCl2. la: mp 73-75 "C. Anal. Calcd for Cl5H&oFeMoOloS: C, 30.54; H, 1.20. Found: C, 30.55; H, 1.14. IR (KBr disk): v(c=o) 1713(s) cm-l; v(cEoj 2082 (s), 2032(s), 2000(s), 1983(s), 1942(s), 1860(s)cm-l. 1H NMR (CDC13): 6 3.92 (s, 3H, CHd, 5.48, 5.66 (9, q, 2H, H3, H4), 6.02 (t, 2H, H2, H5) ppm. MS (EI, Mog8),mlz (relative intensity): 592 (M+, 1.4), 564 [(M - COY, 1.31, 536 [(M - 2CO)+, 2.41, 508 [(M - 3CO)+, 1.31, 480 [(M - 4CO)+, 3.41, 452 [(M - 5CO)+, 6.71, 424 [(M - 6CO)+, 12.81, 396 [(M - 7CO)+, 7.71, 368 [(M - 8CO)+, 7.31, 533 [SFeCoMoCsH4(CO)8+,1.4],505[SFeCoMoC&C0)7+, 1.2],477 [SFeCoMoCfi(Cole+,2.81,449 [SFeCoMoC&&(C0)5+,4.41,421 [SFeCoMoCfi(CO)4+,7.41, 393 [SFeCoMoCsH4(C0)3+,4.51 365 [SFeCoMoCsH4(CO)z+,4.41, 337 [SFeCoMoC5HdCO)+,1.51,309 [SFeCoMoC5H4+,6.21, 301 [SFeCoMo(CO)z+, 1.41, 273 [SFeCoMo(CO)+, 1.11, 245 [SFeCoMo+, 1.51. Compound lb. The workup for lb-e was similar to that of the preparation of la. To the flask described above were added 528 mg (2.0 mmol) of Mo(CO)6, 320 mg(2.0 mmol) of Et02CC5HDa,and 20 mL of THF. The solution was refluxed for 15h. After the reaction of the resulting q5-EtOzCC5H&Io(C0)3Na with 458 mg (1.0 mmol) of FeCoz(C0)9@3-S),305 mg (50%)of l b as a black solid was obtained. lb: mp 74-75 "C. Anal. Calcd for C16HgCoFeMoOloS: c, 31.82; H, 1.50. Found: C, 31.67; H, 1.44. IR(KBr disk): v(c=o) 1719(s)cm-'; v ( c 4 )2077 (s), 2018(s), 1991(s), 1963(s), 19OO(s)cm-'. lH NMR (CDC13): 6 1.32 (t, 3H, J = 7.2 Hz, CH3), 4.30 (q, 2H, J = 7.2 Hz, CHz), 5.40, 5.58 (9, q, 2H, H3, H4), 5.96 (t, 2H, H2, H5) ppm. MS(E1, Mog8),mlz (relative intensity): 606 [M+, 0.71, 550 [(M - 2CO)+, 2.41,522 [(M - 3CO)+, 1.6],494 [(M - 4CO)+, 4.01, 466 [(M - 5CO)+, 8.41, 438 [(M - 6CO)+, 10.81, 410 [(M - 7CO)+, 5.81, 382 [(M - 8CO)+, 4.61, 309 [SFeCoMoC5H4+, 4.6],469 [SFeCoMo(CO)s+,0.61,441 [SFeCoMo(C0)7+,0.71,301 [SFeCoMo(CO)z+,1.51, 245 [SFeCoMo+, 1.91. Compound IC. To the flask described above were added 704 mg (2.0 mmol) of W(CO)6, 292mg (2.0 mmol) of MeOzCCBHDa, and 20 mL of diglyme. The solution was refluxed for 6 h. After the solvent was stripped at reduced pressure, 20 mL of THF and 458 mg (1.0 mmol) of FeCoz (C0)9@3-S) were added. After stirring of the mixture at reflux for an additional lh, 465 mg (68%) of ICas a brown-red solid was obtained. IC: mp 62-64 "C. Anal. Calcd for C15H.1CoFeOloSW: C, 26.58; H, 1.04. Found: C, 26.64; H, 1.02. IR(KBr, disk): v(c-0) 1719(s)cm-l; v ( c 4 02075(s), ) 2028(s), 1985(s), 1946(s),1887(s) cm-l. lH NMR (CDCl3): 6 3.88 ( 8 , 3H, CHd, 5.50, 5.70 (9, q, 2H, H3, H4),6.00 (t,2H, H2,H5)ppm. MS (EI, W19, mlz (relative intensity): 622[(M - 2CO)+, 3.01, 594 [(M 3CO)+, 2.03,566 [(M - 4CO)+,4.41,538 [(M - 5CO)+,9.01,510 [(M - 6CO)+, 12.11, 482 [(M - 7CO)+, 9.01, 454 [(M - 8CO)+, 8.61, 535 [SFeCoWCsH4(CO)5+,0.81, 423 [SFeCoWC5H4(CO)+, 3.61, 395 [SFeCoWC5H4+,4.83, 387 [SFeCoW(CO)Z+,1.91, 359 [SFeCoW(CO)+,1.41, 331 [SFeCoW+, 1.41. Compound Id. To the flask described above were added 704 mg ( 2 0 mmol) of W(CO)6, 320 mg (2.0 mmol) of EtOzCC5H4Na, and 20 mL of diglyme. The solution was refluxed for 6 h. After the reaction of the resulting q5-Et0zCCfiW(C0)3Na with 458 mg (1.0 mmol) of FeCo2(C0)9@3-S),450 mg (65%) of Id as a brown-red solid was obtained. Id: mp 83-84 "C. Anal. Calcd for C16HgCoFeOloSW: C, 27.77; H, 1.31. Found: C, 27.88; H, 1.30. IR (KBr, disk): v(C-0) 172Us) cm-'; v ( c d j 2076(s), 2022(s), 1988(s), 1957(s), 1901 (s) cm-l. lH NMR (CDC13): 6 1.34 (t, 3H, J = 7.2 Hz, CH3), 4.34 (9, 2H, J = 7.2 Hz, CHz), 5.50, 5.68 (9, q, 2H, H3, H4), 5.98 (t, 2H, H2, H5) ppm. MS(E1, WlS4),mlz (relative intensity): 692 [M+ , 5.71, 664 [(M - CO)+,4.9],636 [(M - 2CO)+, 11.41,608[(M - 3CO)+, 9.31, 580 [(M - 4CO]+, 25.61, 552 [(M - 5CO)+,60.71, 524 [(M - 6CO)+, 80.91, 496 [(M- 7CO)+, 48.01, 468 [(M - 8CO)+, 4751,479 [SFeCoWC5H4(C0)3+,3.31,451 [SFeCoWCs&(CO)z+, 551,423 [SFeCoWC5H4(CO)+,5.01,395 [SFeCoWCsH4+,33.61, 555 [SFeCoW(CO)a+, 13.91, 527 [SFeCoW(C0)7+, 9.11, 499 [SFecow(Co)~+, 8.31,471 [SFeCoW(C0)5+,3.21,415 [SFeCoW-

Song et al. (CO)3+,7.21, 387 [SFeCoW(CO)Z+,16.61, 359 [SFeCoW(CO)+, 10.13, 331 [SFeCoW+,22.41. Compound le. To the flask described above were added 704 mg (2.0 mmol) of W(CO)6,260 mg of MeC(O)C5Haa, and 20 mL of diglyme. The solution was refluxed for 6h. After the reaction of the resulting q6-MeC(0)C5H4W(C0)3Nawith 458 mg (1.0 mmol) of FeCoz(CO)g@a-S),458 mg (69%)of l e as a brown-red solid was obtained. le: mp 102-104 "C. Anal. Calcd for C16H7CoFe09SW: C, 27.22; H, 1.07. Found: C, 27.27; H, 0.97. IR (KBr, disk): v(c-oj 168%~) cm-'; vp.0) 2075(s), 2034(s), 2016(s), 1998(s), 1969(s), 1907(m), 1874(m) cm-'. 'H NMR (CDCl3) 6: 2.48 (8,3H, CH3), 5.64,5.82 (q, q, 2H, H3, H4), 6.04 (q, 2H, H2, H5) ppm. MS(E1, WlE4),mlz (relative intensity): 662 [M+, 1.21, 634 [(M - CO)+, 1.91, 606 [(M 2CO)+, 3.1],578 [(M - 3CO)+,2.31,550 [(M - 4CO)+,4.31,522 [(M - 5CO)+, 13.4],494 [(M - 6CO)+, 18.31,466 [(M - 7CO)+, 10.71, 438 [(M - 8CO)+, 26.51, 395 [SFeCoWC5H4+,2.51, 387 [SFeCoW(CO)Z+, 1.431, 359 [SFeCoW(CO)+, 1.31, 331 [SFeCOW+,1.51. Reaction of le with MeMgI. The three-necked flask described above was charged with 200 mg (0.30 mmol) of le and 15 mL of ethyl ether and then 2 mL (0.59 M, 1.18 mmol) of MeMgUether solution was added slowly during stirring. After stirring at room temperature for 3 h, 50 mL of distilled water and 10 mL of (0.167M) of dilute HC1 acid were added. The ether phase was separated from the mixture and the aqueous phase was extracted twice with 10 mL of ethyl ether. The ethyl ether layers were combined and dried with anhydrous MgS04. Solvent was removed under reduced pressure and the residue was subjected to TLC separation using 2:l CHzClz/petroleum ether as eluant. Four orange bands were developed. The third band, as the main band gave 80 mg (39%) of 2 as a brown-red viscous oil. 2: Anal. Calcd for c16H11CoFe09SW: C, 28.35; H, 1.64. Found: C, 28.40; H, 1.55. IR (KBr, disk): V(OHj 3480 (br, m) cm-l; v(c=oj 2073(s), 2016(s), 1984(s), 1893(m)cm-l. lH NMR (CDC13): 6 1.64 (s,6H, 2CH3), 2.28 (s, lH, OH), 5.28-5.64 (m, 4H, C5&) ppm. MS (EI, WlE4), mlz relative intensity): 622 [(M - 2CO)+, 0.081, 538 [(M 5CO)+,0.121, 510 [(M - 6CO)+, 0.181,482 [(M - 7CO)+, 0.421, 454 [(M - 8CO)+, 0.541, 451 [SFeCoWC5H4(CO)z+,0.181, 395 [SF~COWCSH~', 0.101. Reaction of l e with NaB€&. To the flask described above were added 199 mg (0.3 mmol) of le, 11.4 mg (0.3 mmol) of NaBH4,and 10 mL of MeOH. The mixture was stirred at room temperature for 7 h. Solvent was removed under reduced pressure and the residue extracted with CHzClz. The extracts were concentrated and subjected to chromatographic separation on silica gel plates. Two bands were developed when 2:l CHzClz/petroleum ether was used as eluant. From the second orange band, 110 mg (55%)of 3 as a red oil was obtained. 3: Anal. Calcd for C15HgCoFeOgSW: C, 27.14; H, 1.37. Found: C, 27.43; H, 1.48. IR (KBr, disk); v(c=oj2071(s), 2022(s), 1980(s), 1890(s) cm-l; Y(OH) 3427 (br, s) cm-'. lH NMR (CDCl3): 6 1.56 (d, 3H, J = 5.4 Hz, CH3), 2.00-2.32 (m, lH, OH), 4.564.96 (m, lH, CH), 5.16-5.76 (m, 4H, C5H4) ppm. MS (EI, Wls4),mlz (relative intensity): 608 [(M - 2CO)+, 1.11,580 [(M - 3CO)+,0.171, 552 [(M - 4CO)+, 1.41, 524 [(M - 5CO)+, 1.61, 496 [(M - 6CO)+,3.01,468 [(M - 7CO)+;9.31,440 [(M - 8CO)+, 10.8],395 [SFeCoWC5H4+,0.8],471 [SFeCoW(CO)5+,0.91,443 [SF~COW(CO)~+, 0.61,387 [SFeCoW(CO)z+,0.61,359 [SFeCoW(CO)+,3.21, 331 [SFeCoW+, 2.21. Reaction of 3 with EtsOBF4. To a 50 mL flask described above were added 166 mg (0.25 mmol) of 3 and 5 mL of CH2Clz to form a brown-red solution, and then 143 mg (0.75 mmol) of Et30BF4 was added. After the mixture had been stirred for 16 h, solvent was removed under reduced pressure to leave a residue. The residue was subjected to TLC saparation using 2:l CHzClz/petroleum ether as eluant. Seven orange-red bands were developed. From the third band was obtained 51 mg (29%) of 4 as a red viscous oil. 4: Anal. Calcd. for C17H13CoFeOgSW: C, 29.51; H, 1.89. Found: C, 29.69; H, 1.70. IR (KBr, disk): v(c=o)2073(s), 2024(s), 1959(s),1885(m) cm-l.

Cluster Complexes Containing MFeCoS

Table 6. Crystal Data, Data Collection, and Refinement of Compounds 6a and 6b

Organometallics, Vol. 14, NO..^, 1995 105

pressure, 916 mg (2.0 mmol) of FeCoz(CO)g(u3-S) and 20 mL of THF were added. The mixture was refluxed for an additional 1 h. After a workup similar to that of 6a, 570 mg 6a 6b (43%)of 6b was obtained as a brown solid. 6b: mp 139-141 empirical formula ~ dec. Anal. Calcd for C~OHIZCOZF~ZO~BSZWZ: C ~ O H ~ ~ C @ F ~ Z M OCZ~OOI H ~ SI Z~ C O Z F ~ Z O I ~ S ~ W"C C, 27.26; H, fw 1321.79 1145.97 0.92. Found: C, 27.22, H, 0.82. IR (KBr, disk): v(c+) 2075monoclinic triclinic cryst syst (4, 2026(vs), 1978(s) 1886(m) cm-'. v(c-0) 1683(m) cm-l. lH space group P - 1 (NO.2) C2lc (No. 15) NMR(CDCl3): 3.18 (s, 4H, CHzCHz), 5.66,5.80 [q, q, 4H, 2(H3, 26.448(7) alA 7.602(3) H4)1, 5.98-6.18 [m, 4H, 2(H2,H5)] ppm. blA 9.660(4) 8.112(4) CIA 14.687(5) 16.208(3) Reaction of 6a with NaBI&. To the three-necked flask 97.58(3) ddeg described above were added 115 mg (0.1 mmol) of 6a, 7.6 mg 100.72(2) 94.05(2) Bldeg (0.2 mmol) of NaBH4, and 6 mL of methanol. The mixture yldeg 109.50(3) was stirred for 7 h at room temperature. Solvent was removed VIA3 3687(4) 927(1) under reduced pressure and then the residue was extracted 4 Z 1 with CHzClz. The extracts were subjected to TLC using CHz2.38 DJg cm-3 2.05 Clz as eluant. There are three bands on the TLC plates. From 0.28 x 0.05 x 0.75 cryst sizelmm 0.4 x 0.45 x 0.25 the third band was obtained 36 mg (31%) of 7a as a brown 2488 558 F(CW solid. 7a: mp 42-44 "C. Anal. Calcd for C30Hl&ozFez81.80 p(Mo Ka)/cm-' 24.60 radiation Mo K a (1= 0.71069 A) Mo K u (1= 0.71069 A) Moz01&32: C, 31.33; H, 1.40. Found: C, 31.81; H, 1.49. IR tempk 296 296 (KBr, disk): Y ( O H )3435 (br, m) cm-l; v(c+) 2073 (s), 2016 (vs), scan type w - 28 w - 20 1975(vs), 1885(m) cm-l. lH NMR (CDC13): 6 1.96-2.14 (m, 28ldeg (max) 49.9 49.9 4H, CHzCHz), 2.14-2.34 (m, 2H, 20H), 4.58-4.82 (m, 2H, data limitddeg 1" < 0 < 25" 1' < 0 < 25" 2CH), 5.34-5.52 [m, 4H, 2(H3, H4)1,5.52-5.78 [m, 4H, 2(H2, no. of observations 2197 2192 H5)l ppm. ( I > 3.00u(I)) Reaction of 6b with NaBI&. To the three-necked flask no. of variables 277 253 described above were added 138 mg (0.1 mmol) of 6b, 7.6 mg 0.046; 0.051 0.044: 0.048 R; Rw 1.08 1.05 goodness of fit (0.2 mmol) of NaBH4, and 6 mL of methanol. The mixture indicator was stirred for 7h at room temperature. Solvent was removed maximum shift in 0.04 0.05 under reduced pressure and then the residue was extracted final cycle with CHZClz. The extracts were subjected to TLC using CHz1.04 largest peak in final 0.76 Clz as eluant to give three brown-red bands on the plates. From diff maple A-3 the third band was obtained 30 mg (23%) of 7b as a brown solid. 7b: mp 49-51 "C. Anal. Calcd for C ~ O H ~ ~ C O Z 'H NMR (CDCl3): 6 1.22 (t, J = 7.2 Hz, 3H, CHzCHs), 1.50 (d, FezOp.SzWz: C, 27.18; H, 1.22. Found: C, 27.27; H, 1.28. IR J = 7.2 Hz, 3H, CHCH3), 3.40-3.76 (m, 2H, CHz), 4.36 (q, J = (KBr, disk): Y ( O H ) 3443 (br, m) cm-l; v(c-0) 2071(s), 2020(vs), 7.2 Hz, H, CH), 5.28-5.68 (m, 4H, C5H4) ppm. MS (EI, W1"), 1974(vs), 1877 (m) cm-l. lH NMR (CDC13): 6 1.74-2.10 (m, mlz (relative intensity): 692 [M+, 0.91,636 [(M - 2CO)+,2.71, 4H, CHZCHZ),2.50-2.82 (m, 2H, 20H), 4.58-4.86 (m, 2H, 608 [(M - 3CO)+,1.91,580 [(M - 4CO)+,4.41,552 [(M - E O ) + , 2CH), 5.22-5.50 [m, 4H, 2(H3, H4)1, 5.50-5.78 [m, 4H, 2(H2, 5.71, 524 [(M - 6CO)+, 4.21, 496 [(M - 7CO)+, 19.01, 468 [(M H5)l ppm. - 8CO)+, 9.13, 423 [SFeCoWCsH4(CO)+,4.51, 395 [SFeCoWReaction of 7a with EtaOBF4. Method 1. To the 50 mL C5H4+, 2.71, 555 [SFeCoW(CO)B+,0.91, 499 [SFeCoW(CO)6+, flask described above were added 50 mg (0.043 mmol) of 7a 2.53, 471 [SFeCoW(C0)5+,1.13,387 [SFeCoW(CO)Z+,1.31, 359 and 6 mL of CHZC12, after stirring for a while, t o give a brown[SFeCoW(CO)+,4.11, 331 [SFeCoW+, 2.23. From the second red solution, and then 50 mg (0.26 mmol) of Et30BF4 was band was obtained 50 mg (31%)of 5 as a brown-red viscous added. The mixture was refluxed for 0.5 h. Solvent was Z W ZH, : oil. 5: Anal. Calcd for C ~ O H I ~ C O Z F ~ Z O ~C,~ S27.51; removed under reduced pressure and then the residue was 1.23. Found: C, 27.79; H, 1.23. IR (KBr, disk): v(c-0) 2073subjected to TLC using 1:lCHzCldpetroleum ether as eluant (s), 2016(s), 1975(s), 1868(m)cm-l. lH NMR (CDCl3): 6 1.50 to give a pink band, from which 44 mg (90%) of 8a was (d, J = 7.2 Hz, 6H, 2CH3), 4.40-4.80 (m, 2H, 2CH), 5.16obtained as a brown-red viscous oil. 8a: Anal. Calcd for c30' 5.80 (m, 8H, 2C5H4) ppm. H ~ ~ C O Z F ~ Z M O ZC,O31.83; ~ ~ S ZH, : 1.25. Found: C, 31.83; H, Preparations of 6a,b. To the flask described above were 1.45. IR (KBr, disk): v(c-0) 2073(s), 2024(vs), 1967 (vs), 1877 added 258 mg (1.0 mmol) of [N~C~H~C(O)CHZIZ, 528 mg (2.0 (m) cm-l. lH NMR (CDCl3): 6 1.80-2.20 (m, 2H, CHz), 2.20mmol) of Mo(CO)~,and 20 mL of THF. The mixture was 2.60 (m, 2H, CHZ),4.68-5.08 (m, 2H, 2CH), 5.28-5.68 (m, 8H, refluxed for 12h. Upon cooling of the mixture t o room 2CsH4) ppm. temperature, 916 mg (2.0 mmol) of FeCoZ(CO)&S) was added Method 2. To the flask described above were added 50 mg and the mixture refluxed for an additional 1h. Solvent was (0.043 mmol) of 7a and 6 mL of CHzClZ. Upon cooling to 0 "C, removed under reduced pressure t o give a residue. The 50 mg (0.26 mmol) of Et30BF4 was added. After stirring for residue was extracted with CHzClZ, and then the extracts were 2 h at this temperature, TLC showed that no 8a was formed. subjected t o column chromatography. The 2:l CHZCld The reaction mixture continued to be stirred for 2 h at room petroleum ether eluted the unreacted FeCoz(CO)g(us-S)and temperature, and TLC showed that no starting material 7a then a brown-red band. After evaporation of the solvent from was left. After the same workup as before, 42 mg (86%)of 8a the brown-red band solution and drying under vacuum, 360 was obtained. mg (31%)of 6a as a brown solid was obtained. Analytical Method 3. To the flask described above were added 50 mg sample was obtained by recrystallization from 1:2 CHzCld (0.043 mmol) of 7a and 6 mL of CHzClZ. Upon cooling t o 0 "C, petroleum ether. 6a: mp 134-136 "C. Anal. Calcd for c300.05 mL (6.4 M, 0.32 mmol) of aqueous solution of HBF4 was HlzCozFezMozOlaSz: C, 31.44; H, 1.06. Found: C, 31.57; H, added. After stirring for 2 h at this temperature, TLC showed 1.15. IR ( D r , disk): v(cI0) 2077(s), 2028(vs), 1977 (s), 1884 that no 8a was produced. The mixture was then refluxed for (m) cm-l; Y(C=O) 1681 (m) cm-'. lH NMR (CDC13): 6 3.16 ( 8 , an additional 2 h. After the same workup as before, 28 mg 4H, CHzCHz), 5.60,5.72 [q,q, 4H, 2(H3,H4)1,6.08 [t, 4H, 2(H2, (58%)of 8a was obtained. H5)1ppm. Compound 6b. To the flask described above were added Reaction of 7b with Et30BF4. Method 1. To the flask described above were added 57 mg (0.043 mmol) of 7b, 6 mL 258 mg (1.0 mmol) of [ N ~ C ~ H ~ C ( O ) C H 704 Z ]mg ~ , (2.0 mmol) of CHzClZ, and 50 mg (0.26 mmol) of Et30BF4. The mixture of W(CO)6,and 20 mL of diglyme. The mixture was refluxed for 6 h. After the solvent was removed under reduced was refluxed for 0.5 h. After the same workup as above, 50

Song et al.

106 Organometallics, Vol. 14, No. 1, 1995 mg (89%) of 8b as a brown solid was obtained. 8b: mp 3536 "C. Anal. Calcd for C ~ ~ H ~ ~ C O Z F ~ ~ C, O ~27.55; &WZ H,: 1.08. Found: C, 27.68; H, 1.07. IR (KBr, disk): Y(C=O) 2073(s), 2024(s), 1967(vs), 1877(m) cm-l. lH NMR (CDCls): 6 1.80-2.20 (m, 2H, CHz), 2.20-2.60 (m, 2H, CHd, 4.68-5.20 (m, 2H, 2CH), 5.28-5.64 (m, 8H, 2C5H4) ppm. Method 2. To the flask described above were added 57 mg (0.043 mmol) of 7b, 6 mL of CH2C12, and 50 mg (0.26 mmol) of Et30BF4. Then the mixture was stirred for 2h at room temperature. After the same workup as above, 22 mg (39%) of 8b was obtained. Method 3. To the flask described above were added 57 mg (0.043 mmol) of 7b, 6 mL of CHZC12, and 0.05 mL (12.4 M, 0.62 mmol) of aqueous solution of HCI. The mixture was refluxed for 9 h. After the same workup as above, 7 mg (12%) of 8b was obtained. X-ray Structure Determination of 6a and 6b. Samples of 6a and 6b were prepared as detailed above. X-ray quality crystals were grown for 6a and 6b by slow evaporation of their solutions in 2:l CHzClz/hexane. Both crystalline samples were in the form of brown plates. The crystal of 6a or 6b was mounted on a glass fiber in a n arbitrary orientation and

determined on an Enraf-Nonius CAD4 *adometer equipped with a graphite monochromator. Details of the crystals, data collections, and structure refinements are summarized in Table 6. The structures were solved by a direct phase determination method (MULTAN82). The final refinement was accomplishedby the full-matrix least-squares method with anisotropic thermal parameters for non-hydrogen atoms. All calculations were performed on a MICRO-VAX I1 computer using the TAXSAN program system.

Acknowledgment. We are grateful to the National Science Foundation of China and State Key Laboratory of Structural Chemistry for financial support of this work. Supplementary Material Available: Full tables of crystaldata, atomic coordinates and thermal parameters, and bond lengths and angles for 6a and 6b (10 pages). Order information is given on any current masthead page. OM9404310