Ring-Methyl Activation in Pentamethylcyclopentadienyl Complexes. 4

Organometallics , 1995, 14 (2), pp 676–684. DOI: 10.1021/om00002a015. Publication Date: February 1995. ACS Legacy Archive. Cite this:Organometallics...
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Organometallics 1995, 14, 676-684

676

Ring-Methyl Activation in Pentamethylcyclopentadienyl Complexes. 4.l Syntheses, Structures, and Reactions of [( C ~ M ~ ~ C H ~ C ~ ) R U C Iand ( C ORelated )~] Compounds: X-ray Structures of [ ( C ~ M ~ ~ C H ~ C ~ ) R U Cand ~(CO)~] (CsMe4CH20Et)Ru(PPhs)(CO)21(OW Li Fan, Michael L. Turner, Harry Adams, Neil A. Bailey, and Peter M. Maitlis" Department of Chemistry, The University of Shefield, Shefield S3 7HF, England Received August 24, 1994@ The dicarbonyl chloro complex [(C5Me&H2Cl)RuCl(CO)21 (4) is formed by carbonylation (1atm, 20 "C, 5 min) of the dimeric tetramethylfulvene complex [ { ( C ~ M ~ ~ C H ~ ) R (3), UC~~}~I which is in turn made by oxygenation (1atm, 20 "C, 30 min) of [((C5Me5)RuC12}21(1);since both reactions proceed in high yield, 4 is a readily accessible starting material for a range of Cp*-substituted ruthenium complexes. The C-C1 in 4 is readily substituted by nucleophiles to give [(C5Me&H2X)Ru(CO)zCl] (X = OH, OMe, OEt, 0-i-Pr, OPh, OCHzPh, NEt2, H), and by PPh3 (in the presence of NH4PFd to give [(C~M~~CH~PP~~)RU(CO)ZC~]PF~. The Ru-C1 in the alkoxy complexes [(C~M~&H~OR)RU(CO)ZC~I is replaced by reaction with KX to give [(C~Me&H20R)Ru(CO)2Xl(R = Me, X = Br, I, CN, SCN; R = Et, X = Br, I) and Reaction of 4 with by PPh3 in the presence of Ag+ to give [(C~M~~CH~OE~)RU(CO)~(PP~~)I+. KCN or KSCN in MeOH gave a mixture of [(C~,Me&H20Me)Ru(C0)&1,[ ( C ~ M ~ ~ ) R U ( C O ) ~ X ] , and [(C5Me&H&)Ru(C0)2XI (X = CN, SCN). The amines are quaternized; e.g., [(ChMe4X-ray crystal CH2NEt2)Ru(C0)2ClIreacted with Me1 to give [(C~M~~CHZNE~ZM~)RU(CO)~III. structure determinations were carried out for [ ( C ~ M ~ ~ C H ~ C ~ ) R U ((orthorhombic, CO)~C~] a = 18.291(3) b = 11.087(17) c = 6.877(12) V = 1394.6(4)Hi3, 2 = 4, D,= 1.725 g ~ m - ~ , (triclinic, a space group P n m a (D2hI6, No. 62)) and [(C~M~~CH~OE~)RU(CO)~(PP~~)I+(OT~~- 10.496(12) b = 12.509(9) c = 12.738(7) a = 90.25(5)", @ = 93.56(7)", y = 93.85(7)", V = 1666(2) Hi3, 2 = 2, D,= 1.491 g ~ m - space ~ , group P i (Cil No. 2)).

A, A,

A, A,

Introduction The functionalization of unsubstituted cyclopentadienyls is relatively straightforward. However, highly substituted cyclopentadienyls generally form more inert bonds to metals and hence are more interesting as potential catalysts, since ring loss during the catalytic cycles is less of a problem. We2 and other^,^-^ have for some time been seeking ways to synthesize complexes Abstract published in Advance ACSAbstracts, December 1, 1994. (1)Part 3: Gusev, 0. V.; Sergeev, S.; Saez, I.; Maitlis, P. M. Organometallics 1994,13,2059. (2)Miguel-Garcia, J. A,; Maitlis, P. M. J . Chem. SOC.,Chem. Commun. 1990,1472. Gusev, 0.V.;Rubezhov, A. Z.; Miguel-Garcia, J . A,; Maitlis, P. M. Mendeleev Commun. 1991,21. Miguel-Garcia, J. A,; Adams, H.; Bailey, N. A,; Maitlis, P. M. J . Organomet. Chem. 1991, 413,427. Miguel-Garcia, J. A.; Adams, H.; Bailey, N. A.; Maitlis, P. M. J . Chem. Soc., Dalton Trans. 1992,131. See also: Kang, J. W.; Maitlis, P. M. J . Organomet. Chem. 1971,30, 127. Hirai, K.; Nutton, A.; Maitlis, P. M. J . Mol. Catal. 1981,10,203. (3)Hamon, J.-R.; Astruc, D. Organometallics 1988,7,1036.Astruc, D.; Roman, E.; Hamon, J. R.; Batail, P. J . A m . Chem. Soc. 1979,101, 2240. Astruc, D. Acc. Chem. Res. 1986,19,377. (4)Okuda, J. Chem. Ber. 1990,123,1649. Okuda, J.;Zimmermann, K.-H. J . Organomet. Chem. 1988,344,C1. Okuda, J.; Zimmermann, K.-H. Chem. Ber. 1989,122, 1645. Okuda, J.; Zimmermann, K. H. Chem. Ber. 1990,123,1641.Okuda, J.;Zimmermann, IC-H.; Herdtweck, E. Angew. Chem. 1991,103,446; Angew. Chem., Int. Ed. Engl. 1991, 30,430. Okuda, J.; Zimmermann, K.-H. Chem. Ber. 1992,125,637. Okuda, J.; Herdtweck, E.; Zimmermann, K.-H. In Organic Synthesis via Organometallics; Dotz, K. H., Hoffmann, R. W., Eds.; Vieweg: Braunschweig, Germany, 1991;p 207. Zimmermann, K.-H.; Pilato, R. S.; Horvath, I. T.; Okuda, J . Organometallics 1992,11, 3935. (5)Jutzi, P.; Kristen, M. 0.;Dahlhaus, J.; Neumann, B.; Stammler, H.-G. Organometallics 1993,12,2980.Jutzi, P.; Dahlhaus, J. Synthesis 1993,684. See also: Adams, H.; Bailey, N. A,; Colley, M.; Schofield, P. A.; White, C. J . Chem. SOC.,Dalton Trans. 1994,1445. Dahlhaus, J.; Bangel, M.; Jutzi, P. J . Organomet. Chem. 1994,474,55. @

0276-733319512314-0676$09.00/0

A, A,

bearing permethylcyclopentadienyl ligands, e.g. q5-C5Me4R, where R is a pendant arm. Our chief aim in this work is to put a functionality onto the arm which will act as a hand to grasp, orient, and rigidly hold potential reactants to the metal in such a way that highly stereospecific reactions can ensue. It is also of interest to examine the reactivity of such hand substituents when complexed to the metal. Metal complexes with rings bearing handed arms can basically be made in two ways: (i) by reaction of the permethylcyclopentadiene or permethylcyclopentadienyl already bearing the substituent with a suitable metal ~ a l tor~ (ii) , ~ by the functionalization of a metal permethylcyclopentadienyl~ o m p l e x . The ~ , ~ first route has the disadvantages that suitably substituted and functionalized permethylcyclopentadienyls are often hard to make and that, when they are attached to the metal, reagents (e.g. n-BuLi) often need to be used which do not tolerate some functionalities which one would like t o use as a hand. The second approach requires a facile method of activating the ring methyl without destroying the bond (6)Werner, H.; Crisp, G. T.; Jolly, P. W.; Kraus, H.-J.; Krueger, C. Organometallics 1983,2, 1370. Pattiasina, J . W.; Hissink, C. E.; de Boer, J. L.; Meetsma, A,; Teuben, J. H. J . A m . Chem. Soc. 1985,107, 7758. Miller, F. D.; Sanner, R. D. Organometallics 1988, 7, 818. Glueck, D. S.;Bergman, R. G. Organometallics 1990,9,2862. Booij, M.; Meetsma, A,; Teuben, J. H. Organometallics 1991, 10, 3246. Luinstra, G. A,; Teuben, J. H. J . A m . Chem. SOC.1992,114,3361. Horton, A. D. Organometallics 1992,11, 3271. (7)Schock, L. E.; Brock, C. P.; Marks, T. J. Organometallics 1987, 6,232.McDade, C.; Brock, C. P.; Bercaw, J. E. Organometallics 1982, 1, 1629.

0 1995 American Chemical Society

Ring-Me Activation in C a e 5 Complexes

Scheme 1

*

Organometallics, Vol. 14, No. 2, 1995 677

Scheme 2

I

Ru -CI

4 CHZOR 2.

1

CI'

\

I

\

CI-

3a. R =

Me.69, R = Et;

l a . R = I-R.Sa. R = s-Bu 9.R = Ph. 10. R = C,H,OMe,

*CH2

11, R = PhCy,

in particular two terminal metal carbonyls in the IR ( Y (CO) 1988, 2040 cm-l (CH2Cl2)) and the lH and 13C NMR spectra (Tables 2 and 31, which showed a v5-C5to the metal. C-H activation of ring methyls has been Me4CH2 ligand (lH, 6 1.92, 1.98, (s, s, 2 x 2Me), 4.25 reported to occur under the influence of strong bases6 (CH2); 13C,6 9.7, 9.9 (2 x 2Me), 36.7 (CHz), 91.2, 99.9, or by thermal means.' We have recently found that the and 106.1 (Cg ring), and 197.4 (CO)). oxygen-promoted cleavage of a C-H bond takes place An X-ray determination, which showed that the with conspicuous facility in ($-CgMe5)Ru"' complexes molecule comprises a ruthenium atom which is bonded under ambient condition^.^,^ The C-H cleavage in [{($to a chloride, two linear carbonyls, and a (y5-chloroCgMeg)R~C12}21(1)~~ leads to the y6-tetramethylfulvene methy1)tetramethylcyclopentadienyl ligand, confirmed (TMF) complex 3. When the reaction is carried out the structure of 4. The molecule possesses crystallocarefully, an intermediate pox0 complex, [{(r5-CgMe5)graphically imposed mirror symmetry (through the RuRuC1~)~01 (2), can be trapped,ll which spontaneously C1 bond and the unique cyclopentadienyl carbon and its transforms into [((r6-CgMe4CH2)RuC12)21(3)with loss substituent). The conformation is such that the chloof water (Scheme 1).12The Ru(I1) complexes of tetraromethyl substituent is trans t o the chloro ligand, i.e. methylfulvene exhibit interesting reactivity patterns it lies above the gap between the two symmetry-related leading to new chemistry, aspects of which are reported carbonyls, an arrangement similar to that found in [($in this paper. C5Me4Et)Ru(C0)2Br1.l3 The closest lying cyclopentadienyl carbon is that which carries the chloromethyl substituent. The Ru-C1 bond length 2.422(3) is close Results and Discussion to that found for the terminal chlorine in 3 (2.4037(11) (i) Synthesis and Structure of [(q5-CsMe4CH2CI)- A), while the C-C1 bond (C(7)-C1(2) = 1.787(12) A) is Ru(CO)2CIl (4). Reaction of the TMF complex 3 with that expected for a normal organic C(sp3)-C1 bond. carbon monoxide (1 atm, 20 "C, 5 min) gave the There are no noteworthy intermolecular contacts in 4. dicarbonyl chloride complex [(~5-CgMe&H2C1)Ru(CO)~Cll The molecular structure, with atom labeling, is il(4) in high yield (Scheme 2). Since the conversion of 1 lustrated in Figure l. Selected bond lengths and angles into 3 is essentially quantitative, this gives 4 in ca. 85% are given in Table 4. overall yield from 1. The structure of 4 was deduced (ii)Reactions of [(qS-CsMe4CH~CI)Ru(CO)2C11 (4). from its elemental analyses and spectroscopy (Table l ) , (a) With Alcohols and Phenols. Complex 4 underwent facile reactions with nucleophiles at the C-Cl, but (8) Fan, L.; Turner, M. L.; Hursthouse, M. B.; Malik, K. M. A.; the Ru-C1 was attacked only under more forcing Gusev, 0. V.; Maitlis, P. M. J . A m . Chem. SOC.1994,116, 385. (9)Wei, C.;Aigbirhio, F.; Adams, H.; Bailey, N. A,; Hempstead, P. conditions. Thus, heating 4 with methanol, ethanol, D.; Maitlis, P. M. J . Chem. Soc., Chem. Commun. 1991,883. 2-propanol, or 2-butanol in the neat alcohol as solvent (10)Tilley, T. D.; Grubbs, R. H.; Bercaw, J. E. Organometallics 1984, 3,274.Oshima, N.;Suzuki, H.; Moro-Oka, Y. Chem. Lett. 1984,1161. (no base present) gave the appropriate alkoxy complexes Koelle, U.; Kang, B.-S.; Thewalt, U. J . Organomet. Chem. 1990,386, C(~5-CgMe4CH~0R)R~(CO)2Cll (5a,R = Me; 6a, R = Et; 267. Koelle, U.;Kossakowski, J.; Klaff, N.; Wesemann, L.; Englert, 7a, R = i-Pr; Sa, R = s-Bu) (Scheme 2). The reactions U.; Herberich, G. E. Angew. Chem., Int. Ed. Engl. 1991,30,690. (11)Rao, K. M.; Day, C. L.; Jacobson, R. A.; Angelici, R. J . were carried out under reflux in order to expel the HC1 Organometallics 1992,11, 2303. and t o drive them to completion. (12)Fan, L.Ph.D. Thesis, University of Sheffield, 1993. Fan, L.; 3

Wei, C. H.; Aigbirhio, F.; Turner, M. L.; Gusev, 0. V.; Hursthouse, M. B.; Malik, K. M. A,; Maitlis, P. M. Manuscript in preparation.

(13)Adams, H.; Bailey, N. A.; White, C.Inorg. Chem. 1983,22.1155.

Fan et al.

678 Organometallics, Vol. 14,No. 2, 1995 Table 1. Microanalyses, IR Spectra, and Yields of New Complexes microanal.b (%) complex

no. 4 5a 5b 5c

5dd See 6a 6b 6c 7a 8a 9

10 11 12d 12e 13f 14 15 16 17 18a 18dd 19 20

V(CO)~ (cm-I) 1988 2040 1985 2038 1983 2036 1983 2033 1998 2047 1991 2042 1984 2037 1984 2036 1982 2033 1984 2037 1984 2037 1985 2035 1986 2039 1984 2037 2004 205 1 1998 2046 1986 2038 1982 2035 1981 2034 1984 2036 1996 2043 1978 2032 1992 2042 1998 2047 2007 2055

,

H

X

40.2 (39.8) 43.6 (43.6) 38.3 (38.8) 34.9 (34.8) 48.0 (48.3) 44.7 (44.2) 45.4 (45.2) 40.6 (40.4) 36.3 (36.3) 47.1 (46.7) 48.1 (48.0) 51.75 (51.5) 51.1 (50.7) 52.2 (52.6) 48.7 (48.9) 41.7 (41.3) 42.3 (41.9) 49.6 (49.6) 48.3 (48.1) 58.1 (58.2) 31.2 (32.3) 43.9 (44.0) 49.0 (49.1) 48.9 (49.0) 52.6 (53.0)

3.9 (3.9) 4.7 (4.7) 4.1 (4.2) 3.8 (3.8) 4.7 (4.9) 4.4 (4.5) 5.1 (5.1) 4.6 (4.6) 4.2 (4.1) 5.6 (5.6) 5.8 (5.8) 4.7 (4.6) 4.8 (4.7) 4.9 (4.9) 4.1 (4.1) 3.6 (3.5) 4.3 (4.4) 6.0 (5.9) 6.1 (6.0) 5.0 (4.9) 4.3 (4.3) 4.5 (4.6) 4.8 (4.7) 4.0 (4.0) 4.2 (4.6)

19.0 (19.6) 10.0 (9.9) 20.2 (19.9) 28.5 (28.3)

N

S

5d 5e 6a 6b

1.94 (6H), 2.01 (6H)

4.08

6c

2.05 (6H), 2.14 (6H)

4.13

7a

1.85 (6H), 1.91 (6H)

4.00

8a

1.85 (3H), 1.86 (3H). 4.00 (dd) 1.91 (3H), 1.92 (3H)

94

9 10

1.95 (6H), 1.98 (6H) 1.78 (6H), 1.84 (6H)

4.62 4.44

87

11

1.90 (6H), 1.92 (6H)

4.10

91

12d 12e 13 14

2.07 (6H), 2.15 (6H) 2.07 (6H), 2.10 (6H) 1.88 (6H), 1.98 (6H) 1.89 (6H), 1.91 (6H)

3.50 3.95 4.28 (d) 3.06

75

15

1.88 (6H), 1.90 (6H)

3.15

9

16

1.64 (6H), 1.86 (6H)

4.35

75

17"

2.16 (6H), 2.45 (6H)

4.62

18a 18d I& 19

1.90 (15H, Cp*) 2.03 (15H, Cp*) 1.92 (15H, Cp*) 1.34 (6H). 1.92 (6H)

2W

1.80 (6H), 1.82 (6H)

89 92 96 80 8.6 (8.4)

9.4 (9.5) 19.0 (19.2) 27.7 (27.4) 9.3 (9.2) 8.8 (8.9) 8.5 (8.4) 7.4 (7.9) 8.1 (8.2)

5c

90

69 63

15.5 (15.7)

42 3.2 (3.4) 3.2 (3.5) 2.6 (2.8) 2.1 (2.2)

90 78 77 63 80

4.4 (4.4) 5.1 (4.9)

89 92

7.8 (8.1) 6.4 (6.8) 10.2 (10.3) 8.7 (8.6) 8.9 (8.9) 7.2 (7.2) 40.2 (40.2) 10.7 (10.8)

CHzE 4.25 4.00 4.05 4.11 4.07 4.06 4.06

(%)

85

4.0 (4.0) 3.8 (3.7)

4 5a 5b

C5Me4 1.92 (6H), 1.98 (6H) 1.90 (6H), 1.94 (6H) 1.96 (6H), 2.01 (6H) 2.05 (6H), 2.15 (6H) 1.98 (6H), 2.03 (6H) 1.95 (6H), 2.03 (6H) 1.90 (6H), 1.96 (6H)

yield C

Table 2. 'H NMR Spectra (6, mm) of New Complexes complex no.

77 82 73

a In CH2Cl2 solution. Found and calculated (in parentheses). X = C1, Br, I. v(CN) (cm-I): 2122 (18d);2096,2122 (12d);2122 (5d). v(SCN) (cm-I): 2112 (Me); 2113, 2157 (12e); 2112 (5e),fv(OH) (cm-I): 3410

(br).

When the alcohol was a solid, or for other systems where it was not possible to use the reactant alcohol as solvent, a solution of the alcohol in tetrahydrofuran gave the best results; these reactions were accelerated by addition of triethylamine as a base to remove HC1. The (9, R = Ph; complexes [(~5-C5Me~CH~0R)Ru(CO)~(C1)1 10,R = CsHsOMe; 11, R = PhCHz) were obtained in this way by reaction of 4 with phenol, 4-methoxyphenol, and benzyl alcohol, respectively. When complex 4 was reacted with KX (X = Br, I) in acetone, a mixture was obtained that was shown by lH NMR spectroscopy to consist of several products, including [(q5-C5Me4CH2X)Ru(CO)~Cl1and [(a5-C5Me4CH2X)Ru(C0)zXI. The closely similar solubilities prevented separation. However, when the reactions of 4 with KX

E OMe, 3.40 (3H) OMe, 3.40 (3H) OMe, 3.41 (3H) OMe, 3.36 (3H) OMe, 3.40 (3H) OEt, 1.18 (t, 3H), 3.51 (q.4H) OEt, 1.21 (t, 3H), 3.56 (q, 4H) OEt, 1.20 (t, 3H), 3.55 (q, 4H) O'Pr, 1.15 (d, 6H), 3.64 (m, 1H) OSBu,0.86 (t, 3H), 1.12 (d, 3H), 1.48 (m, 2H), 3.38 (m,1H) OPh, 7.25 (m, 5H) OC6&0Me, 3.68 (3H), 6.87 (br, 4H) OPhCH2,4.58 (2H), 7.35 (m, 5H) OH, 2.52 (t, 1H) N(CH2)5, 1.40 (m, 2H), 1.50 (m, 4H), 2.32 (m, 4H) NEt2, 0.98 (t, 6H), 2.45 (q, 4H) NPhz, 6.86-7.30 (m,10H) NEtzMe, 1.46 (t, 6H), 3.28 (s, 3H), 3.80 (q,4H)

4.68 (d), PPh3, 7.50-8.10 (J = 10 Hz) (m, 15H) 4.06 OEt, 1.28 (t, 3H), 3.71 (q, 4H), PPh3, 7.30-7.65 (m, 15H)

In (CD&CO solution. In (CD&CO solution. 31P{IH} NMR 6 18.5 ppm. 31P{IH} NMR: 6 44.4 ppm.

were carried out in methanol or ethanol, the C5Me4CHzC1 ring chlorine was replaced by the alkoxy group, and halide exchange occurred at ruthenium to give [(v5-C5Me4CH20R)Ru(CO)&I (5b,6b,X = Br; 5c,6c, X = I) in excellent yields (Scheme 3). These reactions presumably occur via the primary formation of the alkoxy chloro complex Sa or 6a. Reaction Of 5a with KCN in methanol gave the cyano complex 5d (80%), while reaction of 5a with KSCN gave [(q5-C5Me4CH~0Me)Ru(C0)2SCNl (5e;89%). In contrast, direct reaction of the chloro complex 4 with KCN in MeOH gave a mixture shown by NMR spectroscopy to comprise three complexes: [(~5-C5Me5)Ru(CO)~CNl (1Wca. 77%, see below), [(r5-C&le4CHzCN)Ru(CO)~CN1 (12d;9%), and [(y5-C5Me&HzOMe)Ru(CO)~CNl(5d; 14%) (Scheme 3); the first two were separated and isolated by column chromatography. Complex 4 also reacted with KSCN in methanol to give similar products, but in different ratios, as shown by lH NMR spectroscopy: [(q5-C5Me5)Ru(C0)zSCN1(1%; E%), [(a5C~M~~CH~SCN)RU(CO)~SCNI (12e;75%), and [(r5-C5Me4CHzOMe)Ru(C0)2SCNl(5e;10%);again the last two could be separated and isolated by column chromatography.

Ring-Me Activation in C&le5 Complexes

Organometallics, Vol. 14, No. 2, 1995 679

Table 3. I3C NMR Spectra (6, ppm) of New Complexes CsMe4

co

9.7, 9.9, 91.2, 99.9, 106.1 9.8, 10.0,92.2, 100.5, 105.7 10.0, 10.2, 92.3, 100.4, 105.6 10.7, 10.8, 93.0, 100.3, 104.7 10.3, 10.4,95.0, 101.4, 104.1 9.7, 9.9, 93.1, 100.2, 106.0 9.7, 9.9, 92.6, 100.4, 105.6 10.0, 10.2,92.8, 100.3, 105.1 10.7, 10.8, 92.4, 100.2, 104.6 9.7, 9.8, 92.9, 100.4, 105.5 9.7, 9.8, 9.9, 92.7, 100.4, 105.5, 100.6 9.8, 10.0, 90.5, 100.0, 107.1 9.7, 9.9, 90.8, 100.2, 106.9 9.7, 9.9, 92.1, 100.4, 105.9 10.3, 10.4, 90.3, 101.4, 105.6 10.1, 10.2, 91.7, 100.5, 106.2 9.9, 10.1,98.2, 100.1, 105.7 9.8, 10.4,96.0,100.1, 104.7 9.9, 10.4, 96.0, 100.1, 104.4 9.8,9.9,94.9,99.5,105.6 8.4, 13.8, 86.2, 103.2, 107.8 10.4 (Cp*), 101.1 (Cp*) 9.7 (Cp*), 101.1 (Cp*) 10.0, 10.4, 90.0, 102.4, 105.8 9.8, 9.9, 100.5, 102.4, 107.6

198.4 198.4 197.6 197.6 196.6 197.2 198.0 197.6 197.6 198.0 198.1 197.4 197.5 197.9 195.8 196.4 197.8 198.5 198.5 198.1 197.8 197.5 198.0 206.2 198.0

complex no.

4 Sa

5b 5c

5d 5e 6a 6b 6c 7a

Sa 9 10 11 12d 12e 13 14

15 16 17"

18d 18e 19" 20 a

CH2E

E

36.7 64.8 65.0 65.5 64.5 64.4 62.8 63.0 63.6 60.4 60.7 60.7 61.7 62.2 14.2 28.4 55.3 54.4 47.5 45.7 59.6

OMe, 59.0 OMe, 59.0 OMe, 59.0 OMe, 59; CN, 126.1 OMe, 59.1; SCN, 117.0 OEt, 15.2,66.8 OEt, 15.2, 66.8 OEt, 15.2, 66.7 O'Pr, 22.2 ((CH3)2), 72.3 (CH) O'BU, 9.6 (CH3), 19.1 (CHzCHj), 29.0, (CHZCH~), 77.5 (CH) 114.8, 121.9, 129.7, 158.3 OC&I40Me, 3.68 (Me), 114.7, 116.0, 152.5, 154.5 OCHzPh, 127.9, 128.1, 128.6, 137.4 CN, 115.9 SCN, 111.2

23.7(d),(J=49H~) 61.9

N(CH2)5, 24.1, 26.0, 52.8 NEt2, 11.6,46.2 NPh2, 122.6, 122.9, 129.4, 148.1 NEt2, 10.9,56.9; NMe, 47.1 CN, 128.7 SCN, 117.8 PPh3, 117.0, 118.4, 127.3-138.6 OEt, 15.1, 67.2; PPh3, 127.3-133.1

In (CD3)zCO solution.

Table 4. Selected Bond Lengths (A) and Angles (deg) for [(;tls-C~Me&H~Cl)Ru(CO)~Cl] (4) with Esd's Ru(l)-Cl(l) Ru( 1)-C(2) Ru(l)-C(4) C1(2)-C(7) c(2)-c(3) C(2)-C(2A)

2.422(3) 2.265(7) 2.170(10) 1.787(12) 1.414(10) 1.455(13)

Cl(1)-Ru(1)-C(1) C1(2)-C(7)-C(4)

Ru(1)-C(l) Ru( 1)-C(3) O( 1 -C( ) 1 ) C(3)-C(4) C(4)-C(7)

92.6(2) 109.7(8)

1.882(8) 2.238(7) 1.132(10) 1.432(9) 1.479(13)

Ru(1)-C(1)-O(1) C(1)-Ru(l)-C(lA)

175.2(7) 90.6(5)

Scheme 3 CHpR

.Wll

k

R

5. \co '

RoH

'

co RU 1

n

~

, W I ~ - R / \co ~

co

1

I

Me, X = Br k,R = Me,X = I 6b. R = Et, X = L 5b. R =

4

MrOH

+ KX

8c, R E Et, X = I

Figure 1. View of the structure of [(q5-C5Mc4CH2C1)Ru(CO)2C1](4) from the X-ray determination, with hydrogens omitted.

The complexes 5-11 were air-stable as solids and could readiy be purified by crystallization or chromatography; they were identified by their microanalyses and IR spectra (Table 1)and their NMR spectra. The lH and 13C NMR spectra of the complexes 5-7 and 9-11 (Tables 2 and 3) showed the expected resonances: for example, two signals for the two different types of methyl groups and one signal for the substituted methylene. This showed the C5Me4CH20R ligand to have a symmetric structure. In contrast, the lH NMR

1Ed

12d

M.X=CN

1Be

125

5e. X = SCN

spectrum of complex Sa showed four signals for the ring methyl groups and four signals for the ring CH2O methylene, indicating the presence of a diastereotopic center (0-C(MeXEtXH)) on the C5Me&H20-s-Bu ligand.

Fan et al.

680 Organometallics, Vol. 14, No. 2, 1995

This is a competitive reaction, where the ratio of the two complexes depends on the basicity of the amine. Thus, complex 4 reacted with piperidine and diethyl(14) amine to give [{q5-C5Me4CH~N(CH~)5}Ru(C0)2C11 and [(q5-C~Me4CHzNEtz)Ru(CO)~Cl1 (15)in 74 and 64% yields, respectively. In contrast, no [(q5-C5Me4CHzNPh~)Ru(C0)2ClI(l6) was formed with the weaker base diphenylamine: the only product under these conditions (6a). Improved yields was [(~/~-C~M~~CHZOE~)RU(CO)ZC~] were obtained when the reaction was carried out in diethyl ether, as the products 14 and 15were obtained, essentially pure, after removal of the salt R'2NHzCl by filtration.

Scheme 4 CHPH

I

cnm

P

H20 / NE$

IC'

\A

HCI

13 4

-

[(q5-C5Me4CH,C1)Ru(CO)2C11 + 2NR2H [(q5-C5Me4CH2NR,)Ru(CO),C11 NR2Hz+C114, R,N = piperindyl 15, R = Et

+

1s

6a

20

The spectrum also confirmed that it was the C-C1 which had been replaced by the O-s-Bu group. The IR spectra of the alkoxy complexes showed two v(C0) bands (ca. 1984 and 2037 cm-l), slightly lower than those of the chloro complex 4 (v(C0)1988 and 2040 cm-l), indicating that the alkoxy-substituted Cp* group C5Me4CHzOR is a slightly stronger electron donor to the metal than is C5Me4CHzCl. (b)With Water. Complex 4 reacted only slowly with water; when the reaction was carried out in tetrahydrofuran in the presence of triethylamine, the hydroxy complex 13 was obtained in moderate yield (42%), together with some starting material and other products. The reaction was reversible; treatment of 13 and HC1 quantitatively converted it back into 4, as shown by lH NMR spectroscopy (Scheme 4). The 'H NMR spectrum of complex 13 showed a doublet a t 6 4.28 (J = 7 Hz) due to the substituted CHZand a triplet at 6 2.52 due to the hydroxy group, indicating coupling between them; v(OH) was observed in the IR at 3410 cm-l. ( c ) With Amines. Reaction of the chloro complex 4 with secondary amines (R'zNH) in ethanol gave two complexes, the amino complex [(q5-C5Me&HzNR'z)Ru(C0)~Clland the ethoxy complex [(q5-C5Me4CHz0Et)Ru(C0)zClI (6a) as well as the salt R'zNH2Cl.

+

[(q5-C5Me4CH2C1)Ru(CO)2Cll N R 2 H + EtOH [(q5-C5Me4CHzNR,)Ru(CO)zC11+ [(q5-C5Me,CH20Et)Ru(CO~zCll

Even this last route did not yield 16, which could, however, be obtained in good yield (77%)by the reaction of 4 with HNPh2 in THF in the presence of triethylamine. The amine complexes 14-16 were only slightly airsensitive in the solid but quickly decomposed in solution. The IH and 13C NMR spectra showed two signals for the methyl groups and one for the substituted CH2 of the C ~ M ~ ~ C H Zligand, N R ' ~ indicating that the ligands have symmetric structures. The reaction of [(q5-C5Me4CH~NEt2)Ru(CO)~Cl1 with Me1 gave the quaternary ammonium salt [(q5-C5Me4CHzNEtzMe)Ru(CO)zI]I(17) in 63%yield; the rutheniumbonded chloride was also exchanged for iodide. The

+

[(q5-C5Me4CH2NEt,)Ru(CO),C1] Me1 15

-

[(q5-C5Me4CH,NEt,Me)Ru(C0)2111 17 positive charge on the nitrogen of complex 17 raised the frequency of the v(C0) bands (1996, 2043 cm-) by comparison with those in the uncharged complexes 4-16; it also had the effect of separating the two signals of the ring methyl groups in the 'H NMR spectrum more than in 15. (d) With Borohydride. The reaction of complex 4 with excess NaBH4 in methanol gave two complexes: the methoxy-substituted complex Sa (38%)and the C5(18a;44%). When Me5 complex [(q5-C5Me5)Ru(C0)zC11 the reaction was carried out in THF, only 18a (80%) was obtained.

[(q5-C5Me4CHzC1)Ru(CO),C11+ NaBH,

+ MeOH -

4 [(q5-C5Me5)Ru(CO),C11

+

18a

[(q5-C5Me4CH,0Me)Ru(CO),C11 5a

+

In contrast to these reactions of 4 with NaBH4, studies on related systems found that NaBH4 reacted with [CpRu(PPh3)2Cll in THF with attack at the Ru-

Ring-Me Activation in C&e5 Complexes

bound C1 to afford [CpRu(PPh3)2BH4]14 and with [CpRu(C0)2ClIto give the hydride [C~RU(CO)~HI.'~ ( e ) With Triphenylphosphine. Complex 4 reacted with triphenylphosphine in methanol in the presence of ammonium hexafluorophosphate t o give [(q5-C5Me4C H ~ P P ~ ~ ) R U ( C O ) ~ C ~(19) I [ P Fas ~ ] yellow crystals (Scheme 4). The chlorine on the ring CH2 was again replaced, this time by triphenylphosphine, but no substitution occurred at the metal. The structure was deduced from the 'H NMR and 13C NMR spectra, which showed two singlets for the ring methyl groups (no coupling to phosphorus) and one doublet U P - H ) = 10 Hz and J(P-C) = 49 Hz) for the ligand ring methylene. The coupling of the methylene to phosphorus and the absence of coupling to the ring methyls confirmed that PPh3 is attached t o the ring CH2 and not to the ruthenium. The IR spectrum showed two v(C0) bands at 1998 and 2047 cm-l, close to those for the quaternary ammonium salt 17, in agreement with a positive charge on the complex. Further support for the structure of 19 came from the far-infrared spectra, which showed v(Ru-Cl) at 313 cm-', close to v(Ru-Cl) for complexes 4 (310cm-l), 6a (300 cm-l), and 14 (302 cm-l), each of which bears a terminal Ru-C1 bond. There was no band in this region for [ ( Q ~ - C ~ M ~ ~ C H ~ O E ~ ) R Ubut ( C itO )did ~ Bshow ~ I Y(Ru-Br) a t 240 cm-l. The reaction of 4 with PPh3 in an alcohol in the presence of NH4PF6 did not give [(q5-C5Me4CH20R)Ru(C0)2(PPh3)1[PF61,but this complex was formed in the presence of a silver salt. Thus, the ethoxy complex [($C ~ M ~ ~ C H ~ O E ~ ) R U ((ea) C O reacted ) ~ C ~ I with PPh3 in the presence of silver trifluoromethanesulfonate(AgOTf)to give [(~5-C5Me4CH~0Et)R~(CO)~(PPh~)l[OTfl (20). The lH and 13CNMR spectra showed two signals for the methyl groups and one for the substituted methylene of the C5Me4CHzOEt ligand, indicating a symmetric plane in the cation 20. The IR spectrum showed v(C0) bands a t 2005 and 2054 cm-l, again consistent with a formal positive charge on the complex. The structure of 20 was confirmed by an X-ray determination. The cation comprises a ruthenium which is fairly symmetrically bonded t o a v5-CsMe4CHzOEt ligand, the ruthenium being 1.898A from the mean plane of the ring. Two carbonyls and a triphenylphosphine ligand are also bonded t o the ruthenium. The counteranion is trifluoromethanesulfonate, which shows a rather irregular geometry and is probably disordered. The plane of the antiperiplanar CH20CH2CH3 chain is inclined at 54"t o the mean plane of the five-membered ring, and the chain lies predominantly "below" the plane of the five-membered ring (i.e. on the same side as the ruthenium). The structure is illustrated in Figure 2. Selected bond lengths and angles are given in Table 5.

Conclusion Several novel and unexpected reactions occur in these ruthenium complexes. First and foremost is the facile transformation of the tetramethylfulvene 3 into the r5CsMe4CH2Cl complex 4 by reaction with CO. The simplest explanation is that it proceeds in three (14) Blackmore, T.;Bruce, M. I.; Stone, F. G. A. J . Chem. Soc. A 1971,2376. (15) Davison, A,; McCleverty, J. A.; Wilkinson, G . J. Chem. SOC. 1963,1133.

Organometallics, Vol. 14, No. 2, 1995 681

Figure 2. View of the structure of the cation of [(q5-CsM~~CHZOE~)RU(CO)~(PP~~)I(OT~J (20) from the X-ray determination.

Table 5. Selected Bond Lengths (A) and Angles (deg) for the Cation of [(~~-C~M~~CH~OE~)RU(CO)~(PP~~)](OT~ (20) Ru(1)-P( 1) Ru(1)-C(2) Ru( 1)-C(4) Ru( 1)-C(6) 0(2)-C(2) 0(3)-C(27) C(3)-C(7) C(4)-C(5) CW-C(6) C(6)-C(7) P( 1)-Ru( 1)-C(l) C(l)-Ru(l)-C(2) C(26)-0(3)-C(27)

2.349(3) 1.904( 10) 2.229(8) 2.232(9) 1.121(13) 1.417(18) 1.394(12) 1.413(13) 1.414(12) 1.426( 12)

Ru( 1)-C(l) Ru( 1)-C(3) Ru(1)-C(5) Ru( 1)-C(7) O( 1 1) 0(3)-C(26) C(3)-C(4) C(6)-C(26) C(27)-C(28)

)-a

P(l)-Ru(l)-C(2) 0(3)-C(26)-C(6)

90.3(3) 94.2(4) 111.4(10)

1.892( 10) 2.258(9) 2.227(9) 2.290(9) 1.127(12) 1.416(13) 1.423(12) 1.501(14) 1.428(24) 88.6(3) 109.2(8)

stages: first, breakage of the C1 bridge in 3, then formation of a cationic tetramethylfulvene complex, and finally attack by the ionic chloride at the ring CH2.

+

[{(~6-C5Me4CH,)RuC1,}zl CO

-

[(~6-C5Me4CH2)Ru(CO)C121

-

+

[(q6-C5Me4CH2)Ru(CO)Cl,l CO [(~6-C5Me4CH2)Ru(CO)2CllCl

-

[(~6-C,Me4CH,)Ru(CO),C11C1 [(~5-C5Me4CH2C1)Ru(CO)2Cll In favor of this suggestion is the readiness with which complex 4 itself undergoes nucleophilic substitution a t the CHz-Cl. However, more detailed discussion will need t o await a full kinetic study. Another interesting and useful feature of the chemistry of complex 4 is the ease with which it undergoes nucleophilic substitution at the CHz-Cl, by reagents such as alcohols, amines, etc. This allows the attachment of functionalities which can act as arms and hands. Such reactions are in contrast with those of tetramethylfulvene complexes of other metals (Rh, Ir) we have made,1,2where C5Me4CHz reacts most readily with electrophiles (e.g. MeI, MesSiCl, etc.). In complex 2 C5Me4CH2 is r6 bonded (probably v5:1;1112) and a

Fan et al.

682 Organometallics, Vol. 14, No. 2, 1995

similar bonding situation involving the CH2 may also be present in the transition state for substitution in 4 and related complexes. By comparison, in [(q5-C5H5)M(q4-C5Me4CH2)](M = Rh, Ir) the binding is only q4. Thus, the ruthenium complexes are rather electrophilic (and hence reactive to Y-)at the CH2 while the rhodium and iridium complexes are more nucleophilic at the CH2 and hence more susceptible to attack by Y+. Tetramethylfulvene sandwich complexes of the type [(q5-CsR5)(q6-C5Me4CH2)Ru1+ (R = H, Me) have also been made and have been found to react with nucleophiles in a manner similar to that for complex 4;16this reinforces the idea that the CHZ in a q6-C5Me4CH2 complex is probably inherently electrophilic. Although many of the reactions we have studied involve attack at the Cp* CH2, nucleophiles such as halide do react at the metal center, allowing access to a range of derivatives, [(q5-C5Me4CH20R)Ru(CO)2Xl(X = C1, Br, I). Pseudohalides (CN or SCN) can react both ways, giving a number of products. However, the boundaries of reactivity are not yet clear; for example, triphenylphosphine only displaces the carbon-bonded C1 in complex 4, to give 19, and Ag+ is needed to remove the Ru-bonded C1 in 6a to give 20. These are likely to be kinetic effects, reflecting the relative ease of different reaction paths, rather than thermodynamic. Thus, with suitable reagents, replacement either at the metal or at the ring CH2 can be effected. This makes 4 and its congeners very valuable synthetic intermediates. Further work on these systems is in progress. The ring functionality can be completely removed with borohydride, but unexpectedly, a number of other reagents also remove it and give the q5-C5Me5complex: for example, the formation of 18d by reaction of the chloro complex 4 with KCN. Reaction of [(q5-C5Me4CH2OMe)Ru(C0)2ClIwith KCN in methanol gave [(q5-C5Me4CH2OMe)Ru(CO)zCN]quite cleanly, showing that the C-methoxy complex was not intermediate in the formation of 18d. In addition complex 4 reacted with NaOH plus NaCl in refluxing methanol to give two completely dehalogenated products, [((q5-C5Me5)Ru(CO)2}2l (70%) and [{(q5-C5Me4CH20Me)Ru(CO)2}d (30%), identified spectroscopically. Since small variations in the precise conditions give very different reactions, the routes by which the various types of (q5CsMe5)Ru(C0)2complexes are formed require further investigation, but we presume that hydride species, formed in situ, must be responsible.

Table 6. Atomic Coordinates ( x lo4) and Temperature Factors (biz x 103) for [(q5-C~Me4CH2CI)Ru(CO)~Cll (4) atom RNl) ClU) Cl(2) O(1) (31) C(2) C(3) C(4) (35) C(6) C(7)

X

Y

Z

981(1) -278(2) 3081(2) 1438(4) 1250(4) 683(4) 1398(4) 1834(5) 40(4) 1669(4) 2636(5)

2500 2500 2500 4469(6) 3707(7) 3156(6) 3548(6) 2500 3901(6) 4836(6) 2500

1139(1) 2226(4) -3089(6) 3902(9) 2927(11) - 1876(9) -1411(9) -1054(14) -2404( 11) -1411(12) -776(18)

30(1) 46(1) 70(1) 7~2) 44(3) 29(2) 33(2) 32(3) 40(2) 46(2) 45(4)

"Equivalent isotropic U , defined as one-third of the trace of the orthogonalized Uv tensor.

Preparation of [(t15-CsMe~CHzC1)Ru(CO)~Cll (4). The freshly prepared complex [{(CsMe5)R~Cl2}2]~~ (1;0.49 g) was dissolved in dichloromethane (100 mL) and briefly exposed to air (5 min). A slow stream of carbon monoxide (1a t d 2 0 "C) was then passed through the solution for 0.5 h. The solution was set aside for 2 h; then the solvent was removed in vacuo. The residue was extracted with diethyl ether (3 x 50 mL). This extract was chromatographed on a Florisil column (10 x 4 cm) using diethyl ether to elute a yellow band which gave yellow (4;Oyield crystals of [ ( C ~ M ~ ~ C H ~ C ~ ) R U ( C ) Z C ~0.48 ] g, 82%). (ii) A similar reaction on [(q6-C5Me&H2)RuC12(Me~SO)lg (0.10 g, 0.26 mmol) gave yellow crystals of [(q5-C5Me&H2C1)Ru(CO)2Cll (4; 0.066 g, 70%). X-ray Structure Determination of [(~S-CsMe&H&l)Ru(C0)~Cll(4). Crystal data for Cl~H14C1202Ru: M , =

Reactions were carried out under nitrogen using standard Schlenk-line techniques; those involving silver salts were protected from light. Solvents and reagents were purified and dried by standard methods and were distilled under nitrogen immediately prior t o use. Microanalyses were performed by the Sheffield University Microanalysis Service and are listed, together with yields and IR spectra, in Table 1. IR spectra were recorded as KBr disks on a Perkin-Elmer PE1710 Fourier transform spectrometer or as solutions in a CaF2 solution cell with computerized subtraction of the solvent. 'H and 13CNMR spectra (Tables 2 and 3) were recorded on Bruker AM250, AC250, and WH400 instruments using the solvent or tetramethylsilane as internal standard.

362.22; crystallized from ether as yellow oblongs; crystal dimensions 0.35 x 0.2 x 0.16 mm; orthorhombic, a = 18.291(3) A, b = 11.087(17) A, c = 6.877(12) A, V = 1394.6(4) A3, Z = 4, D, = 1.725 g ~ m - space ~ , group Pnma (D%l6,No. 621, Mo Ka radiation (2 = 0.710 69 A), p(Mo Ka)= 14.77 cm-l, F(OO0) = 719.94. Three-dimensional, room-temperature X-ray data were collected in the range 3.5 < 20 < 50" on a Nicolet R3 diffractometer by the w-scan method. The 1008 independent reflections (of 1486 measured) for which IFl/o(lFI) > 3.0 were corrected for Lorentz and polarization effects and for absorption by analysis of 10 azimuthal scans (minimum and maximum transmission coefficients 0.377 and 0.527). The structure was solved by direct methods and refined by blocked-cascade leastsquares methods. The molecule possessed crystallographically imposed mirror symmetry. Hydrogen atoms were included in calculated positions and refined in the riding mode. Refinement converged at a final R = 0.0537 (R, = 0.0541, 85 parameters, mean and maximum 6/a 0.002, 0.012), with allowance for the thermal anisotropy of all non-hydrogen atoms. The minimum and maximum final electron densities The weighting scheme w-l = u2were -1.16 and 0.73 e k3. (F)+ 0.00154(F)2was used in the latter stages of refinement. Complex scattering factors were taken from the program package SHELXTL17 as implemented on the Data General DG30 computer. Table 4 lists selected bond lengths and angles, and atomic coordinates and temperature factors are contained in Table 6. Preparation of [(q5-C&Ie&HzOMe)Ru(C0)&l] (5a). A solution of [(C5Me4CH2Cl)Ru(C0)2C11(4; 0.1 g, 0.28 mmol) in methanol (30 mL) was refluxed for 6 h. After it was cooled, the solution was evaporated in vacuo to dryness and the residue crystallized from diethyl ether-pentane, to give yellow C O0.088 ) ~ C ~g,] 89%).[(q5crystals of [ ( C ~ M ~ ~ C H ~ O M ~ ) R U ((5a; C5Me&HzOEt)Ru(CO)zCl] (6a;yield 92%), [(q5-C5Me4CH20i-Pr)Ru(CO)zCl] (7a; yield 87%), and [(q5-C5Me4CH20-sBu)Ru(C0)2Cl] (8a;yield 91%) were made similarly.

(16) Koelle, U.; Grub, J. J. Orgunomet. Chem. 1985, 289, 133. Kirchner, K.; Dasgupta, S.; Schmid, R. J. Chem. Res., Synop. 1993, 340.

(17)Sheldrick, G. M. SHELXTL, an integrated system for solving, refining and displaying crystal structures from diffraction data (Revision 5.1): University of Gottingen, Gottingen, Germany, 1985.

Experimental Section

Ring-Me Activation in C f l e s Complexes

Organometallics, Vol. 14, No. 2, 1995 683

Table 7. Atomic Coordinates ( x lo4) and Temperature Preparation of [ ( q s - C ~ e ~ C H ~ O M e ) R u ( C(54. O ~ ~ I[(q5l Factors (A2 x 103) for C ~ M ~ ~ C H ~ O M ~ ) R U(5c) ( C Owas ) ~ I made ] (96% yield) by re[(~5-C~Me,CH~OEt)Ru(CO)~(PPh3)3(oTf) (20) fluxing [(q5-C5Me4CH2C1)Ru(C0)2C1] (4)in methanol containing NaI. [(q5-C5Me4CH20Me)Ru(CO)2Brl(5b;yield 92%), [(q5atom X Y Z Uegn C ~ M ~ & H ~ O E ~ ) R U ( C O yield ) ~ B 90%) ~ I ( ~[(v5-C&fe4CH20Et)~; 1609(1) 3177(1) 3238( 1) Ru(C0)211(6c;yield 0.12 g, 94%), [(q5-C5Me40Me)Ru(CO)2CNl 2751(2) -270(2) 21 8 l(2) (5d; yield 80%), and [(q5-C5Me4CH20Me)Ru(CO)2SCNl (5e; 2899(7) 1416(6) 4224(6) yield 89%)were made similarly from 5a. Reactions with ROH 3965(6) 5218(6) 536(7) or R2NH and Et3N in THF gave [(q5-C&fe4CH20CsH5)Ru(CO)21865(6) 1956(6) 3997(7) Cl] (9;yield 69%), [(q5-C5Me4CH2OC6H40Me)Ru(CO)2Cl1 (10; 2076(7) 3820(7) 2389(8) 889(8) 3663(7) 4455(8) yield 63%),[(q5-C5Me4CH20Bz)Ru(CO)2Cl](11;yield 75%),and 4766(7) 2267(7) 1644(8) [(q5-C5Me4CH2NPh2}Ru(C0)2C11 (16;yield 77%). 4803(7) 3078(7) 2663(8) Preparation of [(q5-CsMe4CHzOH)Ru(CO)~Cll (13). Wa40 15(7) 2854(7) 3501(8) ter (0.20 mL) and Et3N (0.1 mL) were added to a solution of 299 l(8) 3490(7) 1909(7) [(q5-C5Me4CH2C1)Ru(CO)2Cll (4;0.10 g, 0.28 mmol) in THF (15 3980(7) 1534(7) 1861(8) mL). The solution was refluxed for 2 h. During this time, 2182(7) 888(7) -92(8) the solution turned orange. After the solution was cooled, the 1766(7) 638(7) 1052(9) solvent was removed in vacuo, the residue extracted with 1356(9) -345(8) 1171(11) 1288(8) 161(11) -1078(9) diethyl ether, and the extract filtered. The concentrated -971(12) -822(9) 1657(10) filtrate was chromatographed on a silica column (10 x 2.5 cm), 2 129(9) 142(8) - 1095(9) using diethyl ether as eluent, and gave yellow crystals of [(r51820(7) - 1397(8) 2779(7) C ~ M ~ ~ C H ~ O H ) R U ( C(13; O ) ~0.04 C ~ ]g, 42%). - 1789(8) 846(7) 2344(8) Preparation of [(q5-C~Mes)Ru(CO)zC11 (Ma). Sodium 2810( 11) -2602(10) 114(9) borohydride (0.05g) and [(q5-C5Me4CH2C1)Ru(CO)2Cll( 4 0.045 3774( 11) -3029( 10) 406( 1 1) g) in THF (10 mL) were stirred (6 h/20 "C). The solvent was 1365(11) 4237(9) -2678( 10) removed in vacuo and the residue extracted with diethyl ether - 184l(8) 209 1(8) 3752(8) - 1167(8) 1845(7) and chromatographed on silica gel to give yellow crystals of 39 17(7) -245 l(9) 2003(8) 3938(8) [(q5-C5Mes)Ru(CO)2C1](Ma; 0.036 g, 80%). 1719(10) -3096(11) 4837( 10) Preparation of [{q5-CsMe4CH~(CH~)5}Ru(CO)~Cll (14). -2448( 12) 5696( 10) 1318(9) Complex 4 (0.12 g, 0.33 mmol) was dissolved in diethyl ether -1217(12) 1172(10) 5687(9) (20 mL), and piperidine (0.27 mL, 2.7 mmol) was added. The 4796(8) -570( 10) 1420(9) solution was refluxed (10 h, 20 "C); during this time, a white 1277(9) 3647( 10) 2702(8) solid precipitated. After it was cooled, the solution was 1420(15) 47 11(15) 1140(11) filtered. The concentrated filtrate was chromatographed on 2 109(18) 271( 12) 4941( 15) 506(7) 3732(9) 1134(10) a silica column t o give yellow crystals of [{q5-C5Me&H2N2128(9) 5582(8) 679(10) (CH2)5}Ru(C0)2Cl](14; 0.11 g, 90%). [{q5-C5Me4CH2NEt2}56 13(9) 2869( 11) 3958(9) Ru(C0)2C1] (15; 78%) was made similarly. 3456(9) 3843( 10) 4750(9) Preparation of [(qS-C~Me~CH~PPh3)Ru(CO)~C11[PF~l 3 154(14) 7237(21) 6392(19) (19). Complex 4 (0.16 g, 0.44 mmol), NH4PF6 (0.23 g, 1.4 3418(8) 81 12(13) 6970( 17) mmol), and PPh3 (0.15 g, 0.57 mmol) were reacted (5 h, 20 "C) 3941(10) 6726( 15) 6097( 17) in methanol (5 mL). After removal of the solvent yellow 2964(21) 6763(18) 7503( 18) crystals of [(q5-CsMe4CH2PPh3)Ru(C0)2C11[PF61 (19; 0.26 g, 7080(3) 1988(3) 5529(4) 7624( 13) 2423(18) 82%) were obtained from CH2C12-Et20. 4435( 16) 1876(8) 6036(7) 5 140(9) Preparation of [(q5-C&le4CH~OEt)Ru(CO)~PPhsl [OTfl 1283(8) 7645( 12) 6102( 15) (20). A solution of AgOTf (0.07 g, 0.27 mmol) and PPh3 (0.07 g, 0.27 mmol) in CHzClz (5 mL) was added to complex 6a (0.05 a Equivalent isotropic U , defined as one-third of the trace of the g, 0.135 mmol) dissolved in CHzClz (20 mL). After the mixture orthogonalized Urjtensor. was stirred (5 h, 20 "C), the solvent was removed and the residue crystallized from CH2C12-Et20 t o give pale yellow thermal anisotropy of all non-hydrogen atoms. Minimum and crystals of [(q5-C~Me4CH~OEt)Ru(C0)2PPh31[PF~l (20;0.06 g, maximum final electron densities were -1.86 and 2.57 e A-3. 73%). The weighting scheme 1 o - I = d(F) 0.00200(F)2was used in X-ray Structure Determination of [(q5-CsMe4CHzOEt)the latter stages of refinement. Complex scattering factors Ru(CO)z(PPh3)1[0Tfl(20). Crystal data for C33H34F306were taken from the program package SHELXTL17 as implePRuS: M , = 747.73, crystallized from dichloromethane-ether mented on the Data General DG30 computer. Table 5 lists as pale yellow blocks; crystal dimensions 0.55 x 0.25 x 0.175 selected bond lengths and angles, and atomic coordinates and temperature factors are contained in Table 7. mm; triclinic, a = 10.496(12)A, b = 12.509(9)A, c = 12.738(7) A, a = 90.25(5)", /3 = 93.56(7)", y = 93.85(7)", V = 1666(2)A3, Preparation of [(q5-CsMe5)Ru(CO)zCN1 (18d) and [(a52 = 2, D,7 1.491 g ~ m - space ~ , group P1 (Cil No. 21, Mo Ka C&Ie4CHzCN)Ru(CO)&Nl (12d). Complex 4 (0.2 g, 0.55 radiation (1 = 0.710 69 A), p(Mo Ka) = 6.25 cm-', F(OO0) = mmol) and KCN (0.2 g, 3.08 mmol) were refluxed in methanol 763.92. (20 mL; 5 h, 20 "C). The solvent was removed in vacuo and the residue chromatographed on a silica column with MeOHThree-dimensional, room-temperature X-ray data were colEt20 (1:lO) as eluent to give a colorless band which yielded lected in the range 3.5 < 28 i45" on a Nicolet R3 diffractowhite crystals of [(q5-CsMes)Ru(CO)2CNl(0.14 g, 77%) and a meter by the o-scan method. The 3732 independent reflections pale yellow band which gave yellow crystals of [(q5-C5Me4CH2(of 4667 measured) for which iFl/a(lFI) > 3.0 were corrected CN)Ru(C0)2CN] (0.017 g, 9%). for Lorentz and polarization effects and for absorption by Preparation of [(q5-CsMe4CH~SCN)Ru(C0)~SCNl (12e) analysis of 4 azimuthal scans (minimum and maximum (5e). [(q5-C5Me4and [(q5-C5Me4CH~0Me)Ru(CO)~SCNl transmission coefficients 0.546 and 0.593). The structure was CH2Cl)Ru(C0)2Cl](4;0.15 g) and KSCN (0.18 g) were refluxed solved by direct methods and refined by blocked-cascade leastin methanol (20 mL, 5 h). After the mixture was cooled, the squares methods. Hydrogen atoms were included in calculated solvent was removed in vacuo and the residue was crystallized positions and refined in the riding mode. Refinement confrom MeOH-Et20 to give orange crystals of [(r5-C5Me4verged a t a final R = 0.0813 (R, = 0.0827, 406 parameters, (12e;0.126 g, 75%). The mother liquor CH~SCN)RU(CO)~SCN] mean and maximum 6/a 0.006, 0.039), with allowance for the

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684 Organometallics, Vol. 14, No. 2, 1995 was chromatographed on a silica column; elution with Et20 gave a yellow band which gave yellow crystals of [(v5-C5Me4CH20Me)Ru(C0)2SCNl(5e; 0.016 g, 10%). The complex [(v5C~M~~)RU(CO)~SCNI, identified sPectroScoPicallY, W a s also detected.

Acknowledgment. We thank the ORS for some

Fan et al.

support, Dr. B. F. Taylor for N M R spectra, and Professor M. Vargaftik for helpful discussion. Supplementary Material Available: Tables of bond distances and angles, anisotropic thermal and H atom positional parameters for 4 and 20 (3 pages). Ordering information is given on any current masthead page. OM9406815