Organometallics 1995,14, 4905-4909
4905
Preparation of Bi- and Trimetallic Compounds via (C5H6-q6-C6H5)Cr(C0)d Y.K. Kang and Y.K. Chung* Department of Chemistry and Center for Molecular Catalysis, College of Natural Sciences, Seoul National University, Seoul 151 -742, Korea
Soon W. Lee1 Department of Chemistry, Sung Kyun Kwan University, Suwon 440-746, Korea Received March 27, 1995@
Tricarbonyl(cyclopentadienyl-);16-benzene)chromium (2) and its lithium (or potassium) salt (3), presumably [(C5H4-)76-CsH5Cr(CO)31-,have been used to make bi- and trimetallic compounds. Upon reaction with Fez(C0)9, 2 yields CrFe(C0)6@-r6:r4-CllH10(4). The reaction of 3 with M(C0)3(CH&N)3 (M = Cr, W) and Diazald leads to CrM(C0)5(NO)@-r6:q5-CllHg) (7, M = Cr; 8, M = W). Reactions of 3 with Mn(CO)sBr, CCl(PPh&, and FeCl2 result in the formation of CrMn(CO)s@-y6:r5-C11Hg) (9), C0Cr(C0)3(r~-C4Ph4)@-);1~:1;1~-CllHg) (lo),and CrzFe(CO)s@-r6:r5-C11Hg)2 (ll),respectively. The molecular structure of 11 has been determined by X-ray crystallography.
Introduction
approaches have not been elaborated. In an effort to find general approaches, we recently reported the use Chemical processes involving two or more organomeof the cyclopentadienyl ring in (C5H5-r6-CsHs)Mn(CO)3 tallic units in combination with one another are becomas a x-coordinating ligand t o other organometallic ing of increasing importance.2 Especially heterobimereagents.llJ2 tallic complexes that are resistant to fragmentation are Cyclopentadienyl anions and arene rings are known attractive for studies. A common synthetic strategy to be excellent ligands. Thus, it seems likely that involves the use of difunctional ligands, which are cyclopentadienyl and arene serve as valuable and capable of coordinating t o two different metal centers. important ligands for introduction into heterometallic -C5H4PPh2,3 -C5H4-SiMe2CH2PR2,4 - 0 c H ~ P P h 2 , ~ complexes. We recently found that (C5H5-$-C&)CrX(C5H4I2- (X = CH2, CHMe, C=C, s i M e ~ ) , ~ (co)~ (2) was a good starting material for the synthesis -C5H4(CH2)2PPh2,7fulvalene,*biphenyl? and indenyllO of diary1 heterobimetallic compounds. The synthesis of have been used to construct heterobimetallic com2 was reported by Gottardi et al. (eq l ) . 1 3 pounds. However, the scope of synthetic application to heterometallic compounds is limited because general Abstract published in Advance ACS Abstracts, September 1,1995. (1) X-ray analysis for 11. (2) Gladfelter, W. L.; Geoffroy, G. L. Adu. Organomet. Chem. 1980, 18. 2037. Demerseman, B.: Dixneuf. P. H.: Douelade. J.: Mercier. R. Inorg. Chem. 1982,21, 3942. Albers, M. 0.;R o h s o n , D. J.; Coille, N. J . Coord. Chem. Rev. 1986, 69, 127. (3) Casey, C. P.; Bullock, R. M.; Fultz, W. C.; Rheingold, A. L. Organometallics 1982, I, 1591. Casey, C. P.; Nief, F. Organometallics 1985,4, 1218. Casey, C. P.; Bullock, R. M. Acc. Chem. Res. 1987,20, 167. (4) Schore, N. E. J.Am. Chem. SOC.1979,101,7410. Schore, N. E.; Benner, L. S.; LaBelle, B. E. Inorg. Chem. 1981, 20, 3200. LeBlanc, J. C.; Moise, C.; Maisonnat, A,; Poilblanc, R.; Charrier, C.; Mathey, F. J . Organomet. Chem. 1982,231,C43. Rausch, M. D.; Edwards, B. H.; Rogers, R. D.; Atwood, J . L. J . Am. Chem. SOC.1983,105,3882. (5) Ferguson, G. S.; Wolczanski, P. T. Organometallics 1985,4,1601. Ferguson, G. S.; Wolczanski, P. T. J . Am. Chem. SOC. 1986,108,8293. Ferguson, G. S.; Wolczanski, P. T.; Paranyi, L.; Zonnevylle, M. C. Organometallics 1988, 8, 1967. (6) Cuenca, T.; Padilla, A.; Royo, P.; Parra-Hake, M.; Pellinhelli, M. A.; Tiripicchio, A. Organometallics 1995, 14, 848. Gomez-Sal, P.; de Jesus, E.; Perez, A. I.; Royo, P. Organometallics 1993,12,4633. Plenio, H. Chem. Ber. 1991,124,2185. Ciruelos, S.; Cuenca, T.; Flores, J. C.; Gomez, R.; Gomez-Sal, P.; Royo, P. Organometallics 1993, 12, 944. Reddy, K. P.; Petersen, J. L. Organometallics 1989,8,2107. Levanda, C.; Bechgaard, K.; Cowan, D. 0. J . Org. Chem. 1976, 41, 2700. Kramer, J . A.; Hendrickson, D. N. Inorg. Chem. 1980, 19, 3330. (7) Lee, I.; Dahan, F.; Maisonnat, A,; Poilblanc, R. Organometallics 1994, 13,2743. (8)Ashworth, T. V.; Agreda, T. C.; Hertweck, E.; Hermann, W. A. Angew. Chem., Int. Ed. Engl. 1986,25,289. Gambarotta, S.; Chiang, M. Y. Organometallics 1987, 6, 897. Egan, J. W., Jr.; Petersen, J. L. Organometallics 1986, 5, 906. Lacoste, M.; Astruc, D.; Garland, M.T.; Varret, F. Organometallics 1988, 7, 2253. Vollhardt, K. P. C.; Weidman, T. W. Organometallics 1984, 3, 82.
+ NaCp-
@
1
2
We have explored the utility of compound 2. Herein we report the reactions of 2 or the lithium (or potassium) salt of 2 with organometallic reagents resulting in the (9) Geiger, W. E.; Van Order, N., Jr.; Pierce, T.; Bitterwolf, T. E.; Rheingold, A. L.; Chasteen, N. D. Organometallics 1991, IO, 2403. Elschenbroich, C.; Heck, J. J. J. Am. Chem. SOC. 1979, 101, 6773. Bitterwolf, T. E.; Raghuveer, K. S. Inorg. Chim. Acta 1990, 172, 59. Top, S.; Jaouen, G. J. Organomet. Chem. 1979, 182, 381. Bitterwolf, T. E. J. Organomet. Chem. 1980,252, 305. (10) Bonifaci, C.; Ceccon, A.; Gambaro, A.; Ganis, P.; Santi, S.;Valle, G.; Venzo, A. Organometallics 1993, 12, 4211. Ceccon, A,; Elsevier, C. J.; Ernsting, J. M.; Gambaro, A,; Santi, S.; Venzo, A. Inorg. Chim. Acta 1993, 204, 15. Ceccon, A.; Gambaro, A.; Santi, S.; Venzo, A. J. Mol. Catal. 1991, 69, L1. Ceccon, A,; Gambaro, A.; Santi, S.; Valle, Chem. Commun. 1989,51. Green, M. L. G.; Venzo, A. J . Chem. SOC., H.; Lowe, N. D.; O’Hare, D. J. Chem. Soc., Chem. Commun. 1986,1547. Bonifaci, C.; Ceccon, A.; Gambaro, A.; Ganis, P.; Mantovani, L.; Santi, S.; Venzo, A. J. Organomet. Chem. 1994, 475, 267. Van Order, N., Jr.; Geiger, W. E.; Bitterwolf, T. E.; Rheingold, A. L. J. Am. Chem. SOC. 1987, 109,5680. Bonifaci, C.; Ceccon, A.; Gambaro, A.; Ganis, P.; Santi, S.; Venzo, A. Organometallics 1995, 14, 2430. (11) Chung, T.-M.; Chung, Y. K. Organometallics 1992, 11, 2822. (12)Kim, J.-A.; Chung, T.-M.; Chung, Y. K; Lee, S. W. J . Organomet. Chem. 1995,486, 211. (13) Ceccon, A.; Gambaro, A.; Gorttardi, F.; Mannoli, F.; Venzo, A. J . Organomet. Chem. 1989,363, 91.
0276-733319512314-4905$09.00/00 1995 American Chemical Society
4906 Organometallics, Vol. 14, No. 10,1995 formation of bi- and trimetallic compounds, and we also report the molecular structure of [Cr2Fe(CO)6@-r6:q5CllH&]. In the bi- and trimetallic complexes presented in this report, the metals are not linked by metal-metal bonds but are linked by a diary1 functional ligand in which one metal is bonded to a cyclopentadienyl ligand and the other metal is bonded to the arene ring.
Experimental Section All reactions were conducted under nitrogen using standard Schlenk type flask and cannula techniques. Workup procedures were done in air. Elemental analyses were done at the Korea Basic Science Center or at the Chemical Analytic Center, College of Engineering, Seoul National University. lH NMR spectra were obtained with a Varian XL-200 instrument. Infrared spectra were recorded on a Shimadzu IR-470 (spectra measured as films on NaCl by evaporation of solvent). Mass spectra were recorded with a VG ZAB-E double-focusingmass spectrometer. Compounds (C5H5-)7-CsH5)C~CO)3,13 M(C0)3(CHsCN)3= (M = Cr, W),14CoC1(PPh3)315and Mn(CO)5Br16were synthesized according to the published procedures. Synthesis of CrFe(CO)~~-tls:~4-CllHlo)l 4. Compound 2 (0.30 g, 1.08 mmol) and 30 mL of benzene were placed in a Schlenk flask. Fez(C0)g (1.1 g, 3.0 mmol) was added t o the reaction flask while the flask was vigorously flushed with nitrogen gas. The mixture was refluxed for 6 h. The reaction mixture was cooled to room temperature. Silica gel (2 g) was added t o the reaction mixture, and the solvent was removed by rotary evaporator. After column chromatography with hexane/ether (v/v, l O : l ) , the product was obtained in 54%yield (0.20 g). Mp 193 "C; IR v(C0) 2040,1960,1878 cm-l; 'H NMR (CDC13)6 5.85 (vs, 1 H), 5.68 (m, 1 H), 5.32 (m, 2 H), 5.18 (t, 6.2 Hz, 1H), 5.11 (d, 6.8 Hz, 2 H), 3.25 (m, 1 H), 2.82 (vd, 11.6 Hz, 1H), 2.52 (vd, 11.6 Hz, 1H) ppm. Anal. Calcd for C17H10CrFeOs: C, 48.84; H, 2.41. Found: C, 48.74; H, 2.39. Synthesisof [~-~s-~6-C1~H~)CrFe(CO)elBF4, 5. To 4 (177 mg, 0.42 mmol) dissolved in 20 mL of CH3CN was slowly added Ph3CBF4 (210 mg, 0.63 mmol) in 5 mL of CH3CN via cannula at 0 "C. The resulting solution was stirred for 30 min, and then any solids were filtered off. The filtrate was concentrated to ca. 5 mL, and precipitation was caused adding excess diethyl ether. The precipitates were washed with CHzClz (10 mL x 2). The yield was 195 mg (93%). IR Y (CO) 2116,2068,1960, 1880 cm-l; lH NMR (&-acetone) 6 6.15 (t, 1.71 Hz, 2 H), 6.04 (d, 6.59 Hz, 2 H), 5.91 (t, 1.71 Hz, 2 H), 5.87 (t, 6.10 Hz, 1 H), 5.71 (t, 6.47 Hz, 2 H) ppm. Anal. Calcd for C17HgBF4CrFeOs: C, 40.52; H, 1.80. Found: C, 40.43; H, 1.96. Synthesis of [(Ph-tls-CaHa)Fe(CO)slBF4, 6. NOBF4 (0.05 g, 0.43 mmol) was added to the solution of 4 (0.10g, 0.24 mmol) in 10 mL of CHzCl2 at room temperature. After the resulting solution had been stirred for 1 h, 1 mL of CH3N02 was added t o the reaction mixture. The resulting solution was stirred for 10 min, and then any solids were filtered off. The filtrate was concentrated to ca. 5 mL. Excess diethyl ether was added to the filtrate to precipitate the product. The precipitates were washed with CHzClz (10 mL x 2). The yield was 92%. IR Y (CO) 2112, 2056 cm-l; lH NMR (&-acetone) 6 8.02 (d, 5.61 Hz, 2 H), 7.60 (m, 3 H), 6.75 (m, 2 H), 6.30 (m, 2 H) ppm. Anal. Calcd for C14HgBF4Fe03: C, 45.71;H, 2.46. Found: C, 46.09; H, 2.54. Synthesis of Cr2(CO)a(NO)Cu-tla:tl5-C11H~), 7. Compound 2 (0.278 g, 1 mmol) and 30 mL of THF were placed in a Schlenk flask. n-BuLi (1.25 mmol, 0.5 mL of a 2.5 M solution in (14)Quick, M. H.; Angelici, R. J. Inorg. Synth. 1979, 19, 160. (15)Yamazaki, H.;Wakatsuki, Y. In Organometallic Syntheses; King, R. B., Eisch, J. J., Eds.; Academic Press: New York, 1988; Vol. 4, p 278. (16)Tate, D. P.; Knippe, W. R.; Augl, J. M. Inorg. Chem. 1962, 1 , 433.
Kang et al.
n-hexane) was added dropwise to the reaction flask at 0 "C. After the resulting solution had been stirred for 1 h, a THF solution of Cr(C0)3(CH3CN)3(2.27 mmol, generated in situ in 10 mL of THF) was transferred via cannula to the reaction mixture. The resulting mixture was refluxed for 12 h and then cooled to room temperature. Diazald (0.214 g, 1 mmol) was added to the resulting solution. The solution was stirred for 2 h, and the solvent was removed on a rotary evaporator. The resulting residue was extracted with diethyl ether. To the ether extracts was added silica gel (2 g) in hexane (10 mL). After evaporation of the solvent, flash column chromatography with a mixture of ether and hexane (v/v, 1:20)gave the product (0.397 g, 96%). Mp 185 "C (decomp); IR v(C0) 2008, 1966, 1938, 1879 cm-l, v(N0) 1678 cm-'; 'H NMR (CDC13) 6 4.57 (t, 2.44 Hz, 2 H), 4.48 (m, 4 H), 4.26 (m, 1 H), 4.19 (t, 2.44 Hz, 2 H) ppm. Anal. Calcd for ClsHgCrzNO6: c, 46.28; H, 2.18; N, 3.37. Found C, 46.01; H, 2.06; N, 3.20. Synthesis of CrW(CO)s(NO)01-tls:t16-C11H~), 8. A typical procedure was almost the same as the synthesis of 5, except W(C0)3(CH&N)3is used instead of Cr(C0)3(CH3CN)3. Yield: 73 %. IR v(C0) 2004,1960,1924,1882cm-l, v(N0) 1648 cm-'; 'H NMR (CDC13) 6 4.99 (t, 2.2 Hz, 2 H), 4.56 (t, 2.2 Hz, 2 H), 4.43 (m, 4 H), 4.21 (m, 1 H) ppm. Anal. Calcd for C16H9C, 34.90; H, 1.51; cI"o6w: C, 35.12; H, 1.66;N, 2.56. FOLUI~ N, 2.36. HRMS mlz, M+, calcd 546.9342, obsd 546.9357. Synthesis of CrMn(CO)a(/r-t]8-~6-C11H~)y 9. Compound 2 (0.208 g, 0.75 mmol) and 40 mL of benzene were placed in a Schlenk flask. n-BuLi (1 mmol, 0.4 mL of a 2.5 M solution in n-hexane) was added dropwise to the flask at 10 "C. After the resultant solution had been stirred for 1 h, BrMn(C0)a (0.30 g, 1.12 mmol) was added while the reaction flask was vigorously flushed with nitrogen gas. The mixture was refluxed for 12 h. The reaction mixture was cooled to room temperature. After evaporation of the solvent, the residue was extracted with ether. To the ether extracts was added silica gel (2 g) in hexane (10 mL). After evaporation of the solvent, flash column chromatography with a mixture of ether and hexane (v/v, 1:lO) gave the product (0.123 g, 40%). IR v(C0) 2011, 1965, 1925, 1880 cm-l; lH NMR (CDCl3) 6 4.50-4.35 (m, 4 H), 4.21 (m, 3 H), 3.87 (m, 2 H) ppm. Anal. Calcd for C1.rHscrMnO6: C, 49.0; H, 2.18. Found: c , 48.6; H, 1.84. Synthesisof C O C ~ ( C O ) ~ ( ~ ~ - C ; P ~ ~ ) ~10. -~A ~-~~-C~~H solution of 2 (0.278 g, 1 mmol) in 10 mL of THF was slowly transferred via cannula to a solution of KH (0.05g, 1.25 mmol) in 10 mL of THF at 0 "C. The resulting solution was stirred for 1 h at 0 "C. CoCl(PPh& (0.88 g, 1 mmol) and diphenylacetylene (0.40 g, 1.1 mmol) in 20 mL of toluene were added to the reaction flask while the reaction flask was vigorously flushed with nitrogen gas. The mixture was refluxed for 12 h. The reaction mixture was cooled to room temperature, and removal of the solvent gave yellow crude solids. After recrystallization in hexane, the product was obtained in 43%yield. Mp 206 "C; IR v(C0) 1959,1880 cm-'; 'H NMR (CDCld 6 5.10 (m, 20 H), 5.01 (d, 6.6 Hz, 2 H), 4.90 (t, 1.95 Hz, 2 H), 4.75 (t, 1.95 Hz, 2 H) ppm. HRMS m/z Mf - cr(co)3, calcd 556.1594, obsd 556.1601. Synthesis of CraFe(CO)e01-t18:q6-C11H~)2, 11. Compound 2 (0.278 g, 1 mmol) and 30 mL of THF were placed in a Schlenk flask. n-BuLi (1.25 mmol, 0.5 mL of a 2.5 M solution in n-hexane) was added dropwise to the flask at 0 "C. After the solution had been stirred for 1 h, anhydrous FeClz (0.06g, 0.48 mmol) was added to the reaction flask while it was vigorously flushed with nitrogen gas. The reaction mixture was refluxed for 12 h, cooled to room temperature, and filtered. Removal of the solvent gave crude solids. The crude product was recrystallized by methylene chloride and ether. Yield: 76% (0.223 g). Mp 175 "C; IR v(C0) 1939, 1853 cm-'; lH NMR (CDCl3) 6 5.45-5.25 (m, 10 H),4.50 (t, 1.95 Hz, 4 HI, 4.37 (t, 1.95 Hz, 4 H) ppm. Anal. Calcd for Cz&&r2FeO6: C, 55.11; H, 2.97. Found: C, 54.62; H, 2.90. X-ray Structure Determination of CrzFe(CO)t~@-q~:q~CIIH~)~, 11. All X-ray data were collected with use of an
Organometallics, Vol. 14, No. 10,1995 4907
Mz and M3 Compounds via [(C&-1;16-Cd€~CrfCO)~ Table 1. Crystal Data and Structure Refinement for 11 formula fw cwst - syst -
Table 2. Atomsc Coordinates x104)and Equivalent Isotropic Parameters x 109) for 11
(k2
atom Fe
CzeHlsCrzFeOe 610.27
monoclinic
cc
space group a. A
2, d(calcd),Mg/m3 ;rtsize, mm3 tot. no. of observns no. of unique data (Z > 2dZ)) 28 rangeldeg no. of Darams refined
R1 = (ZIFo- F~I)EIFo/
wR2 = {C[w(FO2- Fc2)2YZ[~(F02)21}"2 GOF on F
20.564(9) 7.858(3) 18.048(3) 124.91(3) 2391.6(14) 4 1.695 0.2 x 0.3 x 0.3 0.710 73 (Mo Ka) 4592 1664 3-50 334 0.0661 0.1737 1.065
Enraf-Nonius CAD4 automated diffractometer equipped with an Mo X-ray tube and a graphite crystal monochromator. A red crystal of 11 having approximate dimensions 0.2 x 0.3 x 0.3 mm3, was used for crystal and intensity data collection. Details on crystal and intensity data are given in Table 1. The orientation matrix and unit cell parameters were determined from 25 machine-centered reflections with 1 2 2 8 < 24". Axial photographs were used to verify the unit cell choice. Intensities of three check reflections were monitored after every 1 h during data collection. Data were corrected for Lorentz and polarization effects. The intensity data were empirically corrected with yj-scan data. All calculations were carried out on a personal computer with the SHELXS-86 and SHELXL-93 programs. The unit cell parameters and systematic absences, hkZ (h k = 2n 11, h0Z ( h or I = 2n 11, and OkO (It = 2n + l ) , indicated two possible space groups: Cc and CWc. A statistical analysis of intensities suggested a noncentrosymmetric space group, and the structure converged only in the space group Cc. The structure was solved by direct methods. All nonhydrogen atoms were refined anisotropically. All hydrogen atoms were positioned geometrically and refined using a ridig model. Final atomic positional parameters for non-hydrogen atoms were shown in Table 2, and the selected bond distances and bond angles are shown in Table 3.
+
+
+
Results and Discussion Recently activation of haloarene by the Cr(C0)3 moiety has been attracting much attention in connection with the formation of bi- and polymetallic compounds via the nucleophilic substitution of ha10gen.l~ Compound 2 was prepared by the formal nucleophilic substitution of fluoride by cyc10pentadienide.l~ Compound 2 is an isomeric mixture and is reacted further without isolation of regioisomers.11J3 Treatment of 2 with Fez(C0)g in refluxing benzene led to the isolation of 4 in 54% yield (eq 2). At first we
+
Fe2(CO)g
-
w 4
expected a dimeric compound with bridging carbonyls [{(C5H4-C6H&r(C0)3}-Fe(C0)212 as a product. In-
z
8754(2) 11852(3) 5647(3) 9120(21) 9200( 22) 10016(24) 10855(20) 10785(19) 9966(17) 9917( 18) 8605(19) 9038(21) 10570(21) 11096(20) 6428(17) 6922(19) 8442(21) 8884(22) 7583(17) 7578(17) 6665(17) 6655(21) 7481(23) 8315(22) 8377(18) 13518(22) 11997(18) 13549(25) 3978(22) 5491(20) 3927(24) 14619(16) 12117(16) 14664(18) 2908(17) 5388(16) 2877(19)
1762(1) 103(1) 3428(1) 43(12) 65(13) 692( 11) 1378(12) 1448(9) 752(10) 814(9) 400(9) 567(11) 1084(12) 1232(12) 2315(9) 2449( 13) 2948( 11) 3133(9) 2719(8) 2755(9) 2104(11) 2141(12) 2831(11) 3523(11) 3445(10) 145(10) -1133(12) 150(10) 3413(12) 4673(11) 3400(14) 167(10) -1911(8) 194(8) 3346(10) 5435(7) 3337(10)
a U(eq)is defined as one-third of the trace of the orthogonalized Utjtensor.
Table 3. Selected Bond Distances (A) and Bond Angles (deg) Fe-C(10) Cr(l)-C(30) Cr(l)-C(4) C(6)-C(7)
2.02(2) 1.84(2) 2.18(2) 1.49(2)
C(lO)-Fe-C(12) C(6)-C(l)-C(2) C(7)-C(8)-C(9)
155.9(6) 115(2) 107.7(13)
Fe-C(7) Cr(l)-C(l) C(1)-C(6) C(30)-0(30) Cr(l)-C(50)-0(50) C(3)-C(4)-C(5) C(7)-C(ll)-C(lO)
2.05(2) 2.26(2) 1.40(2) 1.16(2) 176(2) 121(2) 109(2)
stead, we obtained 4 as the sole product. Compound 4 could be a mixture of two isomers as is the precursor 1. However, according to the lH NMR spectrum of 4, only one isomer was produced. This might be due to isomerization during the reaction. Treatment of 4 with by Ph3CBF4 in CH3CN gave 5 in 93% yield (eq 3). Compound 5 is a reddish crystalline
4
2
Y
X
8965(1) s i s g i ij 7489(1) 6496(10) 5818(10) 5796(9) 6462(11) 7157(9) 7162(8) 7916(8) 8120(10) 8848(9) 9122(8) 8545(11) 9097(9) 9802(10) 10044(8) 9481(10) 8873(7) 8181(8) 7477(9) 6817(10) 6848(9) 7551(12) 8182(10) 6836(9) 5604(11) 5607(10) 8459(10) 8509(9) 7227(9) 7223(9) 5244(8) 5250(7) 8812(8) 8925(7) 6820(8)
+
Ph3CBF4
-
F;e(CO)3+ BF4-
w
(3)
5
compound. According to the carbonyl stretching frequencies of chromium carbonyls attached to the phenyl ring of 4 (1960,1878 cm-l) and of 5 (1960,1880 cm-'1, the positive charge on 6 does not give an appreciable electronic effect t o the chromium carbonyls.
4908 Organometallics, Vol.14, No. 10,1995
Kang et al.
Treatment of 4 with 2 equiv of NOBF4 in CHzClz gave 6 in 92% yield (eq 4).When 4 was treated with 1 equiv 4
+
NOBF4
-
01
w
of NOBF4 a t -10 "C, there was almost no reaction within 3 h. When the reaction temperature was warmed t o room temperature for 6 h, we could see the formation of 6 by checking the IR spectrum. Thus, the reaction seemed to be rather sensitive to the reaction temperature. Compounds of (arene)Cr(CO)zNOwere known t o be rather unstable;18 thus, we did not expect nitrosylation of chromium carbonyl. Instead we expected iron dicarbonyl nitrosyl complex. However, 6 was obtained. With deprotonation, the chromium tricarbonyl moiety was also removed. Several years ago, Rausch et al.19reported the use of phenylcyclopentadienylthallium (PhCpTl)to synthesize organometallic compounds. However, they did not report the synthesis of phenylcyclopentadienyliron derivatives. Instead they reported the formation of ruthenium derivatives, e.g., [PhCpRu(CO)zIzand PhCpRu(C0)2C1. The yields (5%-8%) of the reaction were too low to use in synthetic work. Thus, 6 can be used as a good precursor to make phenyl-substituted cyclopentadienyliron complexes. Compound 2 can be easily lithiated in high efficiency by treatment with n-BuLi. The lithiated compound, presumably 3,was used without isolation. Treatment of 3 with Cr(C0)3(CH3CN)3and then with Diazald led to the isolation of 7 (96%) (eq 5). Single crystals of 7
7(M=Cr) 8(M=W)
suitable for X-ray studies were grown in CH2Clz. However, according t o the X-ray studies,20the crystallographically independent complexes are located in the two crystallographic inversion centers and the complex (17) Ishii, Y.; Ishino, Y.; Aoki, T.; Hidai, M. J . A m . Chem. Soc. 1992, 114, 5429. Li, J.; Hunter, A. D.; McDonald, R.; Santarsiero, B. D.; Bott, S. G.; Atwood, J. L. Organometallics 1992,1 1 , 3050. RichterAddo, G.B.; Hunter, A. D. Inorg. Chem. 1989,28,4063. (18)Connelly, N.G.;Kelly, R. L. J . Chem. SOC.,Dalton Trans. 1974, 2334. Ball, D.E.;Connelly, N. G. J.Organomet. Chem. 1973,55,C24. (19) Singh, P.;Rausch, M. D.; Bitterwolf, T. E. J . Organomet. Chem. 1988,352,273. (20) Crystal data for 7: space group Pi; cell parameters a = 10.590(4) A, b = 10.840(2) A, c = 7.138(3) A, a = 90.10(3)",9, = 102.77(6)",y = 89.94(2)"; 2 = 2; R = 7.64; WR = 20.21. The crystal structure of 7 was solved by Prof. M. S. Lah (Han Yang University, Korea).
Figure 1. ORTEP drawing of compound 7. One of the disordered configurations is shown. with pseudoinversion symmetry is disordered in the crystallographic inversion center with half-occupancy of each orientation. Any discussions about geometry are not meaningful. Thus we only report the ORTEP drawing of 7 (Figure 1). When 3 was treated with W(C0)3(CH&N)3 and then with Diazald, the expected compound 8 (73%) was obtained. Single crystals of 8 suitable for X-ray studies were grown in CHzClz. However, we confronted almost the same problems as in 7. The crystal 8 was disordered in the crystallographic inversion center with halfoccupancy of each orientation. When the nitrosylation was performed by using NOBF4, the yield was rather low. The IR spectra of nitrosyl ligands in 7 and 8 display absorption frequencies at 1678 and 1648 cm-l. As in the case of other cyclopentadienylcompounds, the stretching frequencies of nitrosyl ligands decrease as the central metals become heavier.21 Treatment of 3 with Mn(C0)sBr in refluxing benzene produces the yellow compound 9 in 40% yield (eq 6).The
3
+
Mn(C0)gBr
-
w I
Cr (CQ3
9
yellow solid is air-stable and soluble in organic solvents. The IR spectrum of 9 displays metal carbonyl frequencies a t 2011,1965,1925,and 1880 cm-l. On the basis of intensity and position, the bands at 2011 and 1925 cm-l are assigned to the carbonyl ligands of (cyclopentadienyl)Mn(C0)3.22 Treatment of the potassium salt of 3 with CoCl(PPh3)3 and diphenylacetylene in refluxing THF led t o isolation (21)Hoyano, J. K.;Legzdins, P.; Malito, J. T.Inorg. Synth. 1978, 18, 126. Malito, J.T.;Shakir, R.; Atwood, J. L. J.Chem. SOC.,Dalton Trans. 1980,1253.
Mz and
M3
Compounds via [(CsH,-$-C615)Cr(CO)3]
Organometallics, Vol. 14, No. 10, 1995 4909
of compound 10 (eq 7). At first we wanted to prepare
KH
070
1 yKt 1 coCl(PPh3)~ Ph-Ph
Cr
c9
(CQ3
c 10
10
the cobalt carbonyl compound via CO~(CO)S. However, the expected product was too unstable t o isolate and characterize completely (IR v(C0) 2016,1954, and 1869 cm-l). To increase the stability of cobalt derivative, we used diphenylacetylene as a ligand. During this reaction, diphenylacetylenes were dimerized to give tetraphenylcyclobutadienyl ligands.23 Thus compound 10 was synthesized and characterized fully. Compared to the stability of cobalt dicarbonyl derivative, 10 is much more stable. However, during the purification, 10 slowly decomposed. Treatment of 3 with FeCl2 in THF led to the formation of ferrocene derivative 11 in 76% yield (eq 8). Compound
11
11 is slightly soluble in diethyl ether and chloroform and freely soluble in methylene chloride and acetone. Single crystals of 11 suitable for X-ray studies were grown in CH2C12. The geometry of 11 with the atomic numbering scheme used is depicted in Figure 2, and selected distances and angles are given in Table 3. Compound 11 adopts an eclipse conformation with the phenyl groups located in the same direction. This cofacial arrangement of the two phenyl rings seems to be less favorable.24 Recently, Plenio reported24aan eclipsed 1,l'-orientation of the two substituents of 1,l'bis(3,4-dimethylcyclopenta-1,3-dienyl)ferrocene.For 11 and l,l'-bis(3,4-dimethylcyclopenta-1,3-dienyl)ferrocene, (22)Piper, T.S.;Cotton, F. A.; Wilkinson, G. J. Inorg. Nucl. Chem. 1965,I , 165. Fischer, R. D. Chem. Ber. 1960,93,165. Brown, D.A.; Sloan, H. J.Chem. Soc. 1963,4389.Adams, D.M.;Squire, A. J. Chem. Soc., Dalton Trans. 1974,558. (23)Efraty, A. Chem. Rev. 1977,77, 692. (24)(a) Plenio, H.Organometallics 1992,11,1856. (b) Grossel, M. C.; Goldspink, M. R.; Hriljac, J. A,; Weston, S. C. Organometallics 1991, 10, 851.
Figure 2. ORTEP drawing of compound 11. the stacking of the two n-systems seems t o compensate for the sterically less favorable cofacial 1,l'-orientation of the substituents. The Cp rings are nearly perfect planes and are nearly parallel, the angle between the planes being 3(1)". In the same way, the phenyl rings are nearly perfect planes and are nearly parallel with the dihedral angle being 5(1)". The torsion angle between the cyclopentadienyl ring and the phenyl ring (25(1)")is comparable to the twist angle (27.5") of the phenyl rings in (biphenyl)[Cr(CO)21(-PzMe4).25 We have demonstrated that the cyclopentadiene ring of 2 can be coordinated to the second metal (Fe) by cyclopentadiene or cyclopentadienyl fashions. The cyclopentadienyl ring of the lithiated compound 3 can be coordinated to the second metal (Cr, W, Mn, Fe, or Co), demonstrating incorporation of two different transition metals into a single molecule. Recently, bimetallic compounds containing two transition metal moieties joined t o a diaryl ligand were considered as models for the study of the mixed ~a1ences.l~ This study provides one of the potentially attractive methods of preparing diaryl dinuclear complexes with different electronic and structural requirements. Now we are continuing to study of the properties of the novel bi- and trimetallic compounds.
Acknowledgment. We are grateful to the Korea Science Engineering Foundation (Grant No. 93-05-0002) for support of this research program. Supporting InformationAvailable: Tables of full bond distances and bond angles, anisotropic thermal parameters, and hydrogen atom coordinates for 11 (7 pages). This material is contained in many libraries on microfiche, immediately follows this article in the microfilm version of the journal, and can be ordered from ACS; see any current masthead page for ordering information.
OM950223B (25)Geiger, W. E.;Van Order, N., Jr.; Pierce, T.; Bitterwolf, T. E.; Rheingold, A. L.; Chasteen, N. D. Organometallics 1991,10, 2403.
