Organometallics 1995, 14, 3963-3969
3963
Novel Reactions of the Rhenium Carbyne Complex [(v-C5H5)(co)( coC~HBloH10)RecC&] with Metal Carbonyl Compounds. Crystal Structures of [bFe(lc-CCd&) (lc-co) (Coh(q-C5H5)(COC2HBloHlo)l and [ReCOz(lc3-cCsH5)01-c0)2(c0)5 (9-c5H5)(C2HBioHio) 1 Bin Zhu,la Yong Yu,la Jiabi Chen,*Ja Qiangjin Wu,lb and Qiutian Liulb Laboratory of Organometallics Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China, and Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China Received April 11, 1995@ The reactions of [ ( ~ - C ~ H ~ ) ( C O ) ( C O C ~ H B ~ O H(1) ~O with ) RFez(C0)g ~ ~ C C ~and H ~ ~C02(CO)8 in THF a t -5 to +10 "C gave the novel heteronuclear dimetal bridging carbyne complex [ReFe(u-CC6H5)01-CO)(C0)3(r-C5H5)(COC2HBl~Hl~)l (3) and the heteronuclear trimetal bridging carbyne complex [R~CO~(~~-CC~H~)(~-CO)~(CO)~(~-C~H~)(C~HB~OH~O) (41, respectively. The structures of 3 and 4 were established by X-ray crystallographic studies. The carboranyl group remained bonded to the Re atom via the formacyl group in 3 but was transferred from the formacyl group to the Co atom in 4.
Introduction The current interest in the synthesis, structure, and chemistry of di- and trimetal bridging carbene or carbyne complexes stems from the possible involvement of these species in some reactions catalyzed by organometallic compound^.^!^ Recently, we have reported the reaction between a cationic carbyne complex of rhenium, [(r-CgH5)(C0)2RelCC6H51BBr4,and nucleophiles containing a carbonyliron dianion which gives a dimetal bridging carbene ~ o m p l e x . We ~ have also reported several novel olefin-coordinated dimetal bridging carbene or carbyne complexes by the reactions of olefinligated dimetal carbonyl compounds with aryllithium reagents followed by alkylation with Et30BF4, a most direct, simple, and convenient method for the synthesis A- ~ of dimetal bridging carbene or carbyne c ~ m p l e x e s . ~ number of di- and trimetal bridging carbyne complexes have been synthesized by Stone et al. by reactions of alkylidyne complexes with low-valent metal speciesag Stone et al. have reported the reaction of the monometal carbyne complex [(rl-C5H5)(C0)2W~CC6H4cH3-plwith @Abstractpublished in Advance ACS Abstracts, July 1, 1995. (1)(a) Shanghai Institute of Organic Chemistry. (b) Fujian Institute of Research on the Structure of Matter (X-ray structure analysis). ( 2 )Rofer Depooeter, C. K. Chem. Reu. 1981,81,447. (3)Wilkinson, S. G.; Stone, F. G. A,; Abel, E. W. Comprehensiue Organometallic Chemistry; Pergamon Press: Oxford, U.K., 1982; Vol. 8, p 40. (4) Chen, J.-B.; Yu, Y.; Liu, K.; Wu, G.; Zheng, P.-J. Organometallics 1993,12,1213. (5) Chen, J.-B.; Li, D.-S.; Yu, Y.; Jin, Z.-S.; Wei, G . 4 . Organometallics 1993,12,3885. (6) Chen, J.-B.; Li, D.-S.; Yu, Y . ;Chen, C.-G. Organometallics 1994, 13, 3581. (7) Yu, Y.; Chen, J.-B.; Chen, J.; Zheng, P.-J.Organometallics 1993, 12,4731. (8)(a) Garcia, M. E.; Jeffery, J. C.; Sherwood, P.; Stone, F. G. A. J . Chem. SOC.,Dalton Trans. 1987,1209. (b) Evans, D. G.; Howard, J. A. K.; Jeffery, J. C.; Lewis, D. B.; Lewis, G. E.; Grosse-Ophoff, M. J.; Parrott, M. J.; Stone, F. G. A. J . Chem. SOC.,Dalton Trans. 1986,1723. (c) Ashworth, T. V.; Howard, J. A. K.; Stone, F. G. A. J . Chem. Soc., Dalton Trans. 1980,1609. (d) Abad, J . A,; Delgado, E.; Garcia, M. E.; Grosse-Ophoff, M. J.; Hart, I. J.; Jeffery, J. C.; Simmons, M. S.; Stone, F. G. A. J . Chem. SOC.,Dalton Trans. 1987,41.
0276-7333/95/2314-3963$09.00l0
Scheme 1
F0
BBr4-
(q-C5H5)ReEC-csH5 L
+
LiC-CH
\o/ BioHio
\co
J
I
-80 "C THF
/co
CH&
(q -C5H5)Re=C-c& \
oGc
or acetone
co ,C6H5 * (q-C5H5)Re=C
room temp
\
\o / BlOHlO
C -CH
\o / BioHio
\
CO C-CH
2
1
Fe2(C0)g9 and Co2(CO)8l0t o give a heteronuclear dimetal bridging carbyne complex and a trimetal bridging carbyne complex, respectively. Several years ago, we reported the reaction of a cationic carbyne complex of rhenium, [(7;1-CgH5)(C0)2Re=CC6H5lBBr4, with 1-lithio-o-carboraneto afford the unexpected carbyne complex [ ( ~ ~ - C ~ H ~ ) ( C O ) ( C O C ~ H B ~ O Hlo)RerCC6H5] (l),in which a bulky icosahedral ocarboranyl moiety is bound t o a CO to form a carboranylcarbonyl group, in addition to the expected carbene complex [(~~-C~H~)(CO)ZR~=C(C~HB~OH~O)(C~H~ (2)" (Scheme 1). We are now interested in examining the reactivities of this novel carbyne complex 1 and investigating the effect of the bulky icosahedral carboranyl group on the reactions it undergoes. Thus, we have ~~~
(9) Busetto, L.; Jeffery, J. C.; Mills, R. M.; Stone, F. G. A.; Went, M. J.; Woodward, P. J . Chem. Soc., Dalton Trans. 1984,101. (10) Chetcuti, M. J.; Chetcuti, P. A. M.; Jeffery, J . C.; Mills, R. M.; Mitrprachachon, P.; Pickering, S. J.; Stone, F. G. A,; Woodward, P. J . Chem. SOC.,Dalton Trans. 1982,699.
(ll)Chen,J.-B.;Lei,G.-X.;Xu, W.-H.;Zhang,Z.-Y.;Xu,X.-J.;Tang, Y.-Q.; Sci. Sin., Ser. B 1987,30(1),24.
0 1995 American Chemical Society
3964
Zhu et al.
Organometallics, Vol. 14, No. 8, 1995
Table 1. Crystal Data and Experimental Details for Complexes 3 and 4 formula fw space group a (A) b c (A) a (deg) P (de@
(4)
;g
z
dcalc(g/cm3)
cryst size (mm) ,u(Mo Ka)(cm-l) radiation (monochromatedin incident beam) diffractometer temperature ("C) orientation rflns: no.; range (201, deg scan method data collecn range, 20 (deg) no. of unique data, total with I > 3 d I ) no. of params refined correction factors: max, min (DIFABS)
R" Rwb quality-of-fit indicatop largest shifuesd final cycle largest peak, e/A3 R
=
3
4
ClgHzlOsBloReFe 679.53 Pbca (No. 61) 11.944(8) 13.194(4) 32.06(1) 90 90 90 5053(7) 8 1.79 0.45 x 0.25 x 0.20 54.56 Mo K a (A = 0.710 69 A) Enraf-Nonius CAD4 23 25: 20.20-25.30
CzlHz107b10ReCoz 727.57 P1 (No. 2) 9.850(7) 11.733(6) 13.639(9) 86.32(5) 83.19(6) 66.76(7) 1438(4) 2 1.84 0.52 x 0.26 x 0.30 54.34 Mo K a (A = 0.710 69 A) Enraf-Nonius CAD4 23 25; 13.93-15.30 20-0, 2-52 5642,4284 370 1.3182,0.7667 0.051 0.059 1.47 0.01 2.25
20-0,
2-50 4984,1218 155 1.433, 0.700 0.062 0.068 1.28 0.14 1.63
XllFol - lFcll~lFol. R, = [Zw(lFoI - IFcI)2EwIFo1211'2; w = lhz(lFol).Quality of fit = [X.w(lFal-
IFc1)2/(Nobservns
-N
P ~ ~ ~ ~ ~
"C with petroleum ether/CHzClz (51) as the eluant. The brown-red band was eluted and collected. The solvent was removed from the brown-red eluate in vacuo, and the crude product was recrystallized from petroleum ether/CHzClz at -80 "C to give 40 mg (76%, based on 1) of brown-red crystals of 3 (mp 100-102 "C dec). IR ( Y C O ) : in hexane, 2000 vs, 1990 vs, 1980 s, 1855 m cm-'; in KBr, 2020 vs, 1990 vs, 1975 s, 1855 m, 1575 cm-l. 'H NMR (CD3COCD3): 6 7.50-7.00 (m, 5H, C6H5), 5.95 (s, 5H, C5H51, 4.55 (m, l H , C2HBloHlo), 3.20 (m, Experimental Section 10H, CzHBlfilo). MS: m/e 483 [M+ - H - 2CO - Fe(C0)3], 336 [C5H5ReFe(CO)]+,308 [C5H5ReFel+, 252 [CsHsReI+, 143 All manipulations were carried out under a prepurified Nz [C~HBloHlol+.Anal. Calcd for C19Hz105BloReFe: C, 33.58; H, atmosphere using standard Schlenk techniques. All solvents 3.12. Found: C, 33.73; H, 3.05. employed were dried by refluxing over appropriate drying Reaction of 1 with Coz(C0)e To Give [ReCo~@sagents and stored over 4 A molecular sieves under a n Nz CC~H~)O~-CO)~(CO)~(~-C~~)(C~HB~OH~O)I (4). To a stirred atmosphere. Tetrahydrofuran (THF) and diethyl ether (EtzO) solution of 1 (50 mg, 0.093 mmol) in 30 mL of THF a t -10 "C were distilled from sodium benzophenone ketyl, petroleum was added 175 mg (0.512 mmol) of c o ~ ( C 0 ) The ~ . mixture was ether (30-60 "C) from CaHz, and CHZC12 from PzO5, while warmed to 0 "C and stirred a t 0-10 "C for 15 h, during which toluene was distilled from sodium. The neutral alumina time the orange-red solution gradually turned dark red to dark ( 4 2 0 3 ; 100-200 mesh) used for chromatography was deoxybrown. After vacuum removal of the solvents, the dark purple genated at room temperature under high vacuum for 16 h, residue was chromatographed on A203 (neutral)a t -15 to - 10 deactivated with 5%w/w Nz-saturated water, and stored under "C with petroleum ether as the eluant. After elution of the Nz. [ ( ~ - C ~ H ~ ) ( C O ) ( C O C Z H B ~ O H ~ O (1) ) ~was = Cprepared C~H~I unreacted Coz(C0)~ from the column, a green-yellow band was as previously described." Fez(C0)g and Coz(CO)8were pureluted with petroleum ether/CHZClz/EbO(1O:l:l). The solvent chased from Strem Chemicals, Inc. was removed under vacuum, and the crude product was The IR spectra were measured on a Zeiss Specord-75 and a recrystallized from petroleum ether/CHzClz a t -80 "C to yield Shimadzu IR-440 spectrophotometer. 'H NMR spectra were 54 mg (73%, based on 1)of blackish green crystals of 4 (mp recorded at ambient temperature in acetone-d6 solution with 132 "C dec). IR ( Y C O ) : in hexane, 2050 vs, br, 1870 s cm-'; in TMS as the internal reference using a Varian-200 spectromKBr, 2080 vs, 2020 vs, 1918 s, 1870 s cm-'. lH NMR (CD3eter. Electron ionization mass spectra (EIMS) were run on a COCD3): b 7.94 (m, 3H, C&), 7.55 (m, 2H, 5.87 (s, Hewlett-Packard 5989A spectrometer. The melting points 5H, C5H5),3.99 (m, lH, C2HBd-€lo),3.39 (m, 10H, C~HB1fi10). were determined in sealed, nitrogen-filled capillaries and are MS: m/e (based on lE7Re)588 [M - C5H5 - CCsH5 - 2CO]+, not corrected. 560 [M - C5H5 - CC& - 3co]+,532 [M - C5H5 - CC& Reaction of [(~-C5H5)(CO)(COC~HBloH~~)Re=CC~H~l 4CO]+, 504 [M - C5H5 - CCsH5 - 5co]', 476 [M - C5H5CC& (1) with FedCOh To Give [ReFeOl-CCaHs)Ol-CO)(CO)3(rl- 6COl+, 423 [C5H5ReCo(C0)41+,395 [C5H5ReCo(C0)31+,308 CSH~)(COCZHB~OH~O)] (3). To 42 mg (0.078 mmol) of 1 [CsHsRe(CO)zI+,280 [CsH5Re(CO)I+,252 [CsHsRe]+,143 [CZdissolved in 30 mL of THF at -10 "C was added 57 mg (0.156 HBloHlol+. Anal. Calcd for C21Hz107BloReCoz: C, 31.63; H, mmol) of FedC0)g. The mixture was stirred a t -5 to 0 "C for 2.65. Found: C, 31.47; H, 2.60. 20 h, during which time the bright yellow solution gradually turned brown-red. After the solution was evaporated a t 0 "C X-ray Crystal Structure Determinations of Complexes under vacuum to dryness, the residue was chromatographed 3 and 4. The single crystals of 3 and 4 suitable for a n X-ray on an alumina (neutral) column (1.6 x 10 cm) a t -15 to -10 diffraction study were obtained by recrystallization from
studied the reactions of complex 1 with Fez(C0)g and Coz(C0)8. These gave the novel heteronuclear dimetal bridging carbyne complex and the heteronuclear trim e t a l bridging carbyne complex, respectively. This p a p e r describes a detailed study of these reactions and the structural characterization of the products formed.
Organometallics, Vol. 14, No. 8, 1995 3965
Novel Reactions of a Rhenium Carbyne Complex
Table 2. Positional Parameters and Their Estimated Standard Deviations"for 3 and 4 3 atom
X
-0.0935(1) 0.0878(6)
a
Y
0.0552(1) 0.0488(6)
4 z
B(eq),A2
0.14402(1) 0.1933(2)
-0.111(3) 0.157(3) 0.288(3) 0.006(3) 0.131(2)
0.211(2) 0.232(2) -0.077(3) -0.054(4) 0.123(2)
0.213(1) 0.242(1) 0.189(1) 0.268(1) 0.142(1)
-0.079(4) 0.135(3) 0.216(4) 0.041(4) 0.038(4) 0.052(3) -0.052(4) 0.008(3) 0.025(2) 0.021(3) 0.049(3) 0.064(3) 0.075(4) 0.056(3) -0.194(4) -0.244(4) -0.285(3) -0.265(4) -0.219(4)
0.149(3) 0.160(3) -0.021(3) -0.009(4) 0.136(4) 0.216(3) 0.286(4) -0.045(4) -0.157(3) -0.198(3) -0.302(4) -0.0364(3) -0.326(4) -0.229(3) -0.035(5) -0.060(5) 0.035(4) 0.109(4) 0.056(6)
0.188(1) 0.224(1) 0.197(2) 0.238(2) 0.121(2) 0.086(1) 0.072(2) 0.159(1) 0.153(1) 0.113(1) 0.107(2) 0.140(2) 0.181(2) 0.18%1) 0.095(2) 0.139(2) 0.151(2) 0.119(2) 0.087(2)
0.053(3) 0.180(3) 0.153(5) 0.008(4) 0.018(3) 0.162(4) 0.204(4) 0.110(5) -0.026(5) 0.114(4)
0.337(4) 0.271(3) 0.184(6) 0.194(4) 0.412(3) 0.394(4) 0.308(5) 0.258(5) 0.322(5) 0.391(3)
0.107(2) 0.090(2) 0.048(2) 0.036(2) 0.063(2) 0.079(2) 0.042(2) 0.003(2) 0.022(2) 0.017(2)
X
0.45724(5)
Y
0.14576(4)
B(ed, A2
z
0.22174(3)
0.7448(1) 0.6450(2) 1.030(1) 0.824(1) 0.510(1) 0.324(1) 0.909(1) 0.451(1) 0.683(1) 0.647(1) 0.919(1) 0.791(1) 0.514(1) 0.389(1) 0.808(2) 0.527(2) 0.666(1)
0.0113(1) 0.2395(1) 0.0071(8) -0.087(1) -0.0694(7) 0.3028(7) 0.2874(9) 0.5051(8) 0.2137(9) 0.155(1) 0.009(1) -0.0-47(1) 0.008(1) 0.240(1) 0.264(1) 0.405(1) 0.222(1)
0.1723(1) 0.1246(1) 0.2072(8) -0.0306(7) 0.0906(6) 0.0438(6) 0.147(1) 0.138(1) -0.0925(7) 0.2525(8) 0.195(1) 0.047(1) 0.1379(8) 0.1051(8) 0.136(1) 0.134(1)
0.220(2) 0.263(3) 0.366(2) 0.387(1) 0.292(3)
0.230(3) 0.110(3) 0.065(1) 0.170(2) 0.271(1)
0.282(2) 0.290(2) 0.357(1) 0.386(1) 0.340(2)
0.687(1) 0.637(1) 0.671(1) 0.753(2) 0.803(2) 0.772(1) 0.795(1) 0.792(1) 0.959(1) 0.940(1) 0.757(2) 0.666(1) 0.933(2) 1.026(2) 0.901(2) 0.730(2) 0.750(2) 0.896(2)
0.193(1) 0.318(1) 0.356(1) 0.269(1) 0.144(1) 0.107(1) -0.1646(8) -0.280( 1) -0.276(1) -0.224(1) -0.194(1) -0.226(1) -0.418(1) -0.385(1) -0.337(1) -0.336(1) -0.388(1) -0.455(1)
0.3429(8) 0.368(1) 0.450(1) 0.516(1) 0.497(1) 0.411(1) 0.2396(7) 0.1785(8) 0.192(1) 0.313(1) 0.362(1) 0.273(1) 0.199(1) 0.290(1) 0.394(1) 0.370(1) 0.249(1) 0.323(1)
2.47(2)
-0.010(10
+
+
Anisotropically refined atoms are given in the form of the isotropic equivalent parameter defined as 4/3[u2B(l,l) bZB(2,2) c2B(3,3)
+ ab(cos y)B(1,2)+ adcos p)B(1,3) + bc(cos a)B(2,3)1.
petroleum ethedtoluene and petroleum ether/CHzClz solutions at -80 "C, respectively. The single crystals of approximate dimensions 0.45 x 0.25 x 0.20 mm for 3 and 0.52 x 0.26 x 0.30 mm for 4 were sealed in capillaries under an N2 atmosphere. The X-ray diffraction intensity data for 4984 and 5642 independent reflections, of which 1218 and 4284 with Z > 3a(Z)were observable, were collected with a n Enraf-Nonius CAD4 diffractometer a t 23 "C using Mo Ka radiation within the ranges 2" 5 20 5 50" and 2" 5 28 5 52" for 3 and 4, respectively. The intensity data were corrected for Lorentz and polarization factors. An empirical absorption correction was applied to the data for 3 and 4. The crystal structures of 3 and 4 were solved by direct methods to locate the metal atoms and then by difference Fourier maps to successively locate all the non-hydrogen atoms. The structure was refined with isotropic and anisotropic thermal parameters using the unique reflections with Z > 3a(Z). Final refinement converged to R = 0.062 and R, = 0.068 for 3 and R = 0.051 and R, = 0.059 for 4. All the calculations were performed on a Micro-VAX 3100 computer using TEXSAN. The details of the crystallographic data and the procedure used for data collection and reduction information for 3 and 4 are given in Table 1. The positional parameters and temperature factors for non-hydrogen atoms for 3 and 4 are presented
in Table 2. The selected bond lengths and selected bond angles for 3 and 4 are listed in Tables 3 and 4, respectively.
Results and Discussion
Reaction of [(~-C~H~)(CO)(COC~HB~OH~O)R C&1(1) with Fe2(C0)9 To Form [ReFe@-CC&)@CO)(CO)~(~-C~H~)(COC~HB~OH~O)I (3). (r-Cyclopentadieny1)carbonyU1-carboranylcarbonyl)(phenylcarbyne)rhenium, [ ( ~ ~ - C ~ H ~ ) ( C O ) ( C O C ~ H B ~ O (11, H~~)R~~C was treated with an excess of Fez(C0)g in THF a t -5 t o 0 "C for 20 h. After workup as described in the Experimental Section, the brown-red complex 3, [ReFeO~-CC~H~)(~-CO)(CO)~(~~-C~H~)(COC~HB~OH~O was isolated in 76% yield (Scheme 2). Complex 3 is readily soluble in polar organic solvents such as THF and CH2Clz but is only slightly soluble in nonpolar organic solvents such as petroleum ether. It is very sensitive t o air and temperature in solution but stable for a short period on exposure as the solid t o air at room temperature. Compound 3 is formulated as a heteronuclear dimetal bridging carbyne on the basis of its elemental analysis and IR, lH NMR, and mass spectra, as well as
Zhu et al.
3966 Organometallics, Vol. 14,NO.8,1995 Table 3. Selected Bond Distances Comdexes 3 and 4
(A)'' for
~
Re-Fe Re-C(l0) Re-C(l) Re-C(5) Re-C(21) Re-C(24) Re-C(23) Re-C(22) Re-C(25) Fe-C(l) Fe-C(4) Fe-C(3)
2.682(6) 1.86(4) 1.88(5) 2.04(5) 2.31(5) 2.31(5) 2.31(4) 2.36(5) 2.37(5) 2.39(6) 1.73(6) 1.79(5)
Re-Co(1) Re-Co(2) Co(l)-C0(2) Re-C Co(l)-C Co(2)-C Re-C(3) Re-C(4) Re-C(12) Re-C(l1) Re-C(14) Re-C(l3) Re-C(l5) Co(l)-C(l)
2.669(3) 2.688(2) 2.531(3) 2.01(1) 1.92(1) 1.981) 1.89(1) 1.91(1) 2.21(2) 2.22(2) 2.27(1) 2.27(1) 2.28(2) 1.77(1)
Complex 3 Fe-C(2) 1.86(5) Fe-C(10) 1.91(4) Fe-0(5) 1.98(3) O(l)-C(l) 1.22(5) 0(2)-C(2) 1.14(5) 0(3)-C(3) 1.16(5) 0(4)-C(4) 1.20(6) 0(5)-C(5) 1.31(5) C(lO)-C(ll) 1.50(6) C(ll)-C(12) 1.39(5) C(ll)-C(16) 1.45(5) Complex 4 Co(l)-C(2) 1.82(1) co(l)-c(3) 2.39(1) CO(l)-C(Ol) 2.10(1) c 0 ( 2 ) - c ( 4 ) 2.57(1) c0(2)-c(5) 1.76(1) c0(2)-c(6) 1.83(1) co(2)-c(7) 1.84(1) O(l)-C(l) 1.11(1) 0(2)-C(2) 1.14(1) 0(3)-C(3) 1.17(1) 0(4)-C(4) 1.15(1) 0(5)-C(5) 1.16(1) 0(6)-C(6) 1.12(1) 0(7)-C(7) 1.12(1)
C(12)-C(13) 1.42(5) C(13)-C(14) 1.35(6) C(14)-C(15) 1.42(6) C(15)-C(16) 1.30(6) C(21)-C(25) 1.37(8) C(21)-C(22) 1.46(7) C(22)-C(23) 1.40(6) C(23)-C(24) 1.45(6) Re-Cp(cen)* 2.00 C(24)-C(25) 1.35(6) C(5)-C(6) 1.54(6) C(6)-C(7) 1.62(5) C(ll)-C(12) C(ll)-C(15) C(12)-C(13) C(13)-C(14) C(14)-C(15) C-C(21) C(21)-C(22) C(21)-C(26) C(22)-C(23) C(23)-C(24) C(24)-C(25) C(25)-C(26) C(Ol)-C(O2)
1.30(4) 1.35(3) 1.37(3) 1.41(2) 1.36(2) 1.48(1) 1.40(1) 1.41(1) 1.35(2) 1.39(2) 1.38(2) 1.38(2) 1.64(1)
a Estimated standard deviations in the least significant figure are given in parentheses. Cp(cen) denotes the centroid of the cyclopentadienyl group.
Scheme 2 (q-C5H5)Re=C-CBH~ \
THF
C-CH
\!/
BioHio
3
the single-crystal X-ray diffraction study. In complex 3, the carboranylcarbonyl ligand is bonded to the Re atom via a formacyl group. The oxygen atom of the acyl is coordinated to the Fe atom to satisfy an 18-electron configuration. The IR spectrum and solution lH NMR spectrum of 3 are consistent with the structure in Scheme 2. The IR spectrum (KJ3r) in the YCO region (Experimental Section) of 3 showed an absorption band a t 1855 cm-' attributed to a bridging or semibridging carbonyl ligand, in addition t o three strong terminal CO absorption bands at 2020,1990, and 1975 cm-l, which is indicative of a (C0)3FeRe@-CO)moiety in 3. The weak absorption band a t 1575 cm-l which is characteristic oE the carboranylcarbonyl ligand in 1 demonstrated that the acyl ligand has not been destroyed or converted in the reaction. As compared with starting material 1, the intensity of the acyl absorption band in 3 is weakened, arising from the coordination of the oxygen atom of the formacyl ligand with the Fe atom. The 'H NMR
spectrum of 3 showed the expected proton signals attributed to phenyl, cyclopentadienyl, and carboranyl groups. An X-ray diffraction study was carried out in order to establish firmly the structure of 3. As shown in Figure 1, 3 is a heteronuclear dimetal complex with a bridging carbyne ligand. The Re-Fe bond is bridged by the CC6Hs group, giving a dimetallacyclopropene ring, The Re-Fe distance of 2.682(2) A in 3 is slightly shorter than that found (2.7581(8) A) in the dimetal bridging carbene complex [ReFeCu-CHCsHs)(r-CsHs)(co)6].4The alkylidyne carbon asymmetrically bridges the Re-Fe bond (Re-C(10) = 1.86(4) A, Fe-C(10) = 1.91(4) 8). The Re-C distance (1.86(4) A) is significantly longer than the Re'Ccarbyne bond in 1(1.76(3)A) and is close t o the sum of covalent double-bond radii of Re and C (1.91 A),12which indicates that Re is doublebonded to the carbyne carbon C(10). The Fe-C(l0) distance (1.91 (4) A) not only is shorter than the FeCcarbyne bond in the analogous carbyne complex [FeMo@cc6H4cH3-p)(co)6(17-cs~)] (2.008 A)% but also is shorter than the average distance of the p-C-Fe bonds in diiron bridging carbene complexes [(CsHs)(C0)4Fe201-C(OCzHs)(C6H&'F3-p)}] (2.037 A),5 [Fe2(r-CsHs)z(CO)z@-CO){pC(OCzH5)C6H5}] (2.026 and [Fez(ll-CsHs)z(CO)z(~CO)@-C(OC2H5)C6H&F3-p}](2.004 It is close to the Fe-Ccarbenebond length in monoiron carbene comA)13and [(r4plexes [(C0)4Fe=C(OC2Hs)C6C151(1.887(4) C ~ ~ H ~ ~ ) ( C ~ ) ~ F ~ = C ( O C ~ (1.915(15) H ~ ) C ~ HA).14 ~CH~-OI Therefore, we consider that there also exists partial double-bond character in the Fe-C(l0) bond. The distance between the carbyne carbon C(l0) and phenyl group (C(lO)-C(ll) 1.50(6)A) in 3 is longer than that found (1.43(4) A) in 1, which shows that the conjugation of the benzene ring with the carbyne bond in 3 is weakened. This is consistent with the fact that the proton signals of the phenyl group moved upfield in the 'H NMR spectrum of 3 and the dihedral angle between the benzene ring plane and ReFeC(10) plane of 134.87'. As anticipated from the IR spectrum, of five CO groups, three terminal CO's are attached to the Fe atom and the other two to the Re atom. Among the two CO groups bonded to the Re atom, one is a formacyl bonded to the carboranyl group with an Re-C(5) bond length of 2.04(5) A. The bond angle of Re-C(5)-C(6) is 134', greatly deviating from 120', probably due to the steric bulk of the carboranyl group. The oxygen atom of the acyl is coordinated to the Fe atom, thus giving the Fe atom an 18-electronconfiguration. As a result, the bond length of C(5)-0(5) (1.31(5)A) is much longer than that found (1.13(4)A) in 1. The other CO bonded to the Re atom is a semibridging carbonyl to the Fe atom (ReC(1) = 1.88(5)A, Fe-C(l) = 2.39(6) &. In complex 3, the carboranyl group is retained in the reaction, as can be visualized in the ORTEP diagram of 3 represented in Figure 1. The mechanism for the formation of complex 3 (Scheme 2) is not yet clear. When Fe(C015 was used instead of Fez(C0)~for the reaction under the same (12)Tilzpatrick, P. J.; Page, Y. L.; Butler, I. S . Acta Crystallogr. 1987, B37, 1052. (13) Wang, T.-L.; Chen, J.-B.;Xu, W.-H.; Zhang, S.-W.; Pan, Z.-H.; Acta Chim.Sin. 1987, 1, 85. Tang, Y.-Q. (14)Chen, J.-B.;Lei, G.-X.; Jin, Z.-S.; Hu, L.-H.; Wei, G.-C. Organometallics 1988, 7, 1652.
Novel Reactions of a Rhenium Carbyne Complex
Organometallics, Vol. 14, No. 8, 1995 3967
Table 4. Selected Bond Angles (deg). for Complexes 3 and 4 C(l)-Re-Fe C(5)-Re-Fe C(lO)-Re-Fe C(2 1)-Re- Fe C(241-Re-Fe C(231-Re-Fe C(22)-Re-Fe C(25)-Re-Fe C( 1)-Fe -Re C(41-Fe-Re C(3 )-Fe -Re C(2kFe-Re 0(5)-Fe-Re C(lO)-Fe-Re C(lO)-Re-C(l) C(lO)-Re-C(5) C(lO)-Re-C(21) C(lO)-Re-C(24) C(lO)-Re-C(23) C(lO)-Re-C(22) C(lO)-Re-C(25) C(1j-Re-C(5)
Complex 3 C(l)-Re-C(21) C(l)-Re-C(22) C(l)-Re-C(23) C(l)-Re-C(24) C(l)-Re-C(25) C(3)-Fe-C(10) C(3)-Fe-0(5) C(2)-Fe-C(10) C(2)-Fe-0(5) C(lO)-Fe-0(5) C(5)-0(5)-Fe Re-C( 1)-Fe 0(1)-C( 1)-Fe O(1)-C( 1)-Re 0(2)-C(2)-Fe 0(3)-C(3)-Fe 0(4)-C(4)-Fe C(ll)-C(lO)-Re C(ll)-C(lO)-Fe Re-C(lO)-Fe c~l2~-c~ll~-c~lo~ C(l6)-C(ll)-C(lO)
Co(l)-Re-Co(S) Co(2)-Co(l)-Re Co( l)-Co(2)-Re C -Re- Co( 1) C -Re -Co(2 C-Co(l)-C0(2) C -Coi 1)-Re C-C0(2)-Co( 1) C-Co(21-Re Co(l)-C -Co(2j Co(1)-C-Re Co(21-C-Re C(3)-Re-Co(l) C(3)-Re-Co(2) C(4)-Re-Co(l) C(4I-Re-Co(2 ) C( 1l)-Re-Co( 1) C(ll)-Re-Co(B) C(12)-Re-Co(l) C( 12j-Re-Co(2) C( 13)-Re -Co( 1 C( 13)-Re -Co(2 C(14)-Re-Co( 1j C(14)-Re-C0(2) C( lB)-Re-Co( 1) C(15j-Re-C0(2) C-Re-C(3) C-Re-C(4)
Complex 4 C-Re-C(l1) C-Re-C(l2) C-Re-C(l3) C-Re-C(14) C-Re-C(15) C(3)-Re-C(4) C(3)-Re-C(12) C(3)-Re-C(11) C(3)-Re-C(14) C(3)-Re-C(13) C(3)-Re-C(15) C(4)-Re-C(12) C(4)-Re-C(11) C(4)-Re-C(14) C(4)-Re-C(13) C(4)-Re-C(15) C-Co( l)-C( 1) C-Co(l)-C(2) C-Co(l)-C(01) C( l)-Co( 1)-Fe C(1)-Co(l)-C0(2) C(2)-Co(l)-C0(2) C(2)-Co(l)-Re c(o1)-co(l)-co(2) C(Ol)-Co( 1)-Re C(l)-Co(l)-C(2) c(l)-co(l~-c~ol) C(2)-Co(l)-C(01)
C(5)-Re-C(2 1) C(5)-Re-(22) C(5)-Re-C(23) C(5)-Re-C(24) C(5)-Re-C(25) C(l)-Fe-0(5) C(l)-Fe-C(2) C(l)-Fe-C(3) C(l)-Fe-C(4) C(l)-Fe-C(lO) C(4)-Fe-C(3) C(4)-Fe-C(2) C(4)-Fe-C(10) C(4)-Fe-0(5) C(3)-Fe-C(2) 0(5)-C(5)-C(6) 0(5)-C(5)-Re C(6)- C(5)-Re Cp(cen)b-Re-C(U Cp(cen)-Re-Fe Cp(cen)-Re-C(lO) Cp(cen)-Re-C(5)
a Estimated standard deviations in the least significant figure are given in parentheses. cyclopentadienyl group.
Cp(cen) denotes the centroid of the
conditions, no product 3 was obtained and only starting for 15 h. After removal of the solvent under vacuum, materials were received. Interestingly, Stone et al. the residue was chromatographed on Al2O3, and the reported that the heteronuclear dimetal bridging carcrude product was recrystallized from petroleum ether/ (M = byne complex [(rl-CsH5)(CO)sMFeCu-CCsH4CH3-p)] CH2C12 at -80 "C to give (Scheme 3) a 73%yield of the Mo, W) formed by the reaction of the carbyne complex blackish green complex [(r-CsHs)(CO)zM~CCsH4CH3-p](M = Mo, W) with 1 C ~ H ~ ) ( C ~ H B ~ O(4), HIO ) ] is sensitive to air and which equiv of Fez(C0)g can react further with an excess of temperature in solution but is air-stable as the solid. Fez(C0)g to afford a heteronuclear trimetal bridging On the basis of its elemental analysis, IR, lH NMR, and carbyne complex, [(rl-CgH5)(C0)9MFe2(~3-CC6H4CH3- mass spectra, as well as single-crystal X-ray structure p)19 However, in contrast with [(?pC5H5)(CO)sMFe@determination, it is corroborated that compound 4 is a CC6&CH3-p)], complex 3 did not react with an excess novel heteronuclear trimetal bridging carbyne complex. of Fez(C0)g to give a heteronuclear trimetal bridging Surprisingly, the carboranyl group has been transferred carbyne complex. This may be caused by the steric from the formacyl to a Co atom during the reaction. hindrance of the bulky carboranyl group, which serves The results of the structure analysis (Figure 2) to prevent further reaction of 3 with Fe2(CO)g. Reaction of 1 with COZ(CO)S To Form [ReCoz@~- confirmed that complex 4 is a heteronuclear trimetal bridging complex. However, the carboranyl C C ~ H ~ ) @ - C ~ ) ~ ( C O ) S ( ~ ~ - C ~(4). ~ )Simi(CZ~~O H ~ O ) carbyne I group is directly bonded t o the Co(1) atom, caused by lar to the reaction of 1 with Fez(CO)g,compound 1 was migration of the carboranyl group from the formacyl t o treated with an excess of Co2(CO)s in THF at 0-10 "C
Zhu et al.
3968 Organometallics, Vol. 14,No.8,1995
Figure 1. Molecular structure of 3 showing the atom-labeling scheme.
Figure 2. Molecular structure of 4 showing the atom-labeling scheme. Scheme 3
/coE C - C ~ H S (TJ-C~H~)RB \
O~~'C--CH
\o / BlOHIO
(2) construct an a proximate isosceles triangle (Co(1)Co(2) = 2.531(3) Re-Co(1) = 2.669(3) 8,Re-Co(2) = 2.688(2) A). The metal-metal bond lengths are closely related to that of the known com lex [CoaRe&CCsH4Me-4)(CO)lo](Co-Co = 2.535(1) , average ReCo = 2.70 A).15 The C-Co andp-C-Re distances are C-Co(1) = 1.92(1) 1,-C-C0(2) = 1.95(1) A, and C-Re = 2.01(1) A, respectively, of which the C-Co bond lengths are comparable to that found (average C-Co = 1.89 A) in [ C O ~ R ~ C ~ ~ - C C ~ H ~ M ~while - ~ ) (the CO)~OI,~ C-Re bond length is significantly shorter than that in [ C O ~ ~ C ~ ~ - C C ~ H ~ M(2.189(6) ~ - ~ ) ( C and O)~ is ~ closer I to the sum of covalent double-bond radii of Re and C (1.91 A1.12 The five carbonyl groups are terminally bound to both Co atoms, two to Co(1) and three to C0(2), and the two carbonyl groups bridge or semibridge the Re-Co bonds. Among two carbonyl groups bonded to the Re atom, one (C(3)0(3))is a bridging carbonyl ligand with the Co(1)
i,
THF
+ COZ(C0)8 o-,o"c
-
1
1 - W 5
I
C6H5
B1oH1o
4
the Co atom; the original formacy] is converted into a bridging CO or semibridging CO ligand. The molecule of 4 possesses a trimetallatetrahedrane CCo2Re core. The three metal atoms Re, Co( l ) , and Co-
(15)Jeffery, J. C.;Lewis, D. B.;Lewis, G.E.;Stone, F. G. A. J . Chem. SOC.,Dalton Trans. 1985, 2001.
Organometallics, Vol. 14, No. 8, 1995 3969
Novel Reactions of a Rhenium Carbyne Complex
A,
angle of 60", C(Ol)-C(O2) = 1.64(1) an average B-C atom, thus giving the Re and Co(1) atoms an 18-electron distance of 1.70 and an average B-B distance of 1.77 configuration. The C(3)0(3) ligand is asymmetrically which are close to those found in 111 and 3. bonded t o the Re and Co(1) atoms (Re-C(3) = 1.89(1) Co(l)-C(3) = 2.39(1) The Re-C(3) distance The spectroscopic data showed significant structural (1.89(1) is close to that of the Re-C(termina1 CO) information for 4, shown in Scheme 3. The IR spectrum bond (1.90 A) in 111 and the Re-C(terminal CO) bond (KBr) of 4 showed a semibridging CO absorption band (average 1.97 A) in [Co2Re013-CC6H4Me-4)(co)lo1,'5 at 1918 cm-l and a bridging CO absorption band at 1870 while the Co(l)-C(3) bond length of 2.39(1) is much cm-l, in addition to terminal CO absorption bands at longer than the Co-C(terminal CO) bond lengths (aver2080 and 2020 cm-l. No absorption attributable to the age 1.80 & in 4. The asymmetrical bridging carbonyl acyl function was observed. These are consistent with groups were also found in some di- and trimetal carbothe results of the X-ray diffraction determination of 4 nyl compounds such as Fe2(CO)7dipy,l6Fe3(C0)12,17and (Figure 2). The lH NMR spectrum of 4 showed the Fe3(CO)8(C4H8S)2.'* Cotton et al. considered that this expected proton signals of phenyl, cyclopentadienyl, and asymmetrical bridge linkage of the carbonyl group carboranyl groups. However, the chemical shift of the equilibrates electric charge on the two neighboring carboranyl protons is greatly different from those in 1 metal atoms.16 In 4, since the back-donation of d ( ~ C H4.58 ppm, ~ B 2.88 ~ ppm). ~ H The~ C-H ~ signal electrons from the Co(1) atom to the z* back-bonding moved upfield (6 3.99 ppm), and the B-H resonances orbital of the bridging carbonyl group (C(3)0(3)) is moved downfield (6 3.39 ppm), which suggested that the weaker than that from the Re atom, the electric charge chemical environment of the carboranyl group in 4 is on the Re atom decreased and on the Co(1) atom different from that in 1. In 1 the carboranyl group is increased relatively, thus giving the Re and Co(1) atoms attached t o the electron-poor acyl, but in 4 the carboin an electric charge equilibrium. Another carbonyl ranyl group is bonded to the electron-rich Co metal atom group bonded to the Re atom (C(4)0(4))is a semibridgas shown in Figure 2, thus leading BCH t o move upfield ing carbonyl group with the Co(2) atom (Re-C(4) = and ~ B t o move ~ ~ downfield. H ~ ~ 1.91(1)A,Co(2)-C(4) = 2.57(1) which led the ReC(4)-0(4) bond angle to be 168", greatly deviating from Acknowledgment. We thank the National Natural 180" and closer to the bond angle of Re-C(3)-0(3) Science Foundation of China and the Science Founda- ~ )average (CO)~OI (162"). In [ C O ~ R ~ ( ~ ~ - C C ~ H ~ M ~the tion of the Chinese Academy of Sciences for support of Re-C-0 bond angle is 176".15 this research. Although the carboranyl group migrated, transferring from formacyl to the Co(1) atom, during the reaction, SupportingInformationAvailable: Tables of additional the structure of the carboranyl group in 4 is unchanged. bond lengths and angles and least-squares planes for 3 and 4 The icosahedral carboranyl group has an average bond
A,
A)
A,
A).
A,
A
A,
(16)Cotton, F. A.; Troup, J. M. J . Am. Chem. SOC.1974,96,1233. (17)Cotton, F. A.; Troup, J. M. J . Am. Chem. SOC.1974,96,4155. (18)Cotton, F. A.; Troup, J. M. J . Am. Chem. SOC.1974,96,5071.
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OM9502594
