9814
J. Am. Chem. SOC.1995,117, 9814-9821
1,4-Carbosilylation of 1,3-Dienes via Palladium Catalyzed Three-Component Coupling Reaction Yasushi Obora, Yasushi Tsuji," and Takashi Kawamura Contribution from the Department of Chemistry, Faculty of Engineering, Gifu University, Gifu 501-11, Japan Received May 19, 1995@
Abstract: Three-component coupling reaction of acid chlorides, organodisilanes, and 1,3-dienes achieves 1,4carbosilylationof the 1,3-dienes to afford allylic silanes as the product. Bis(dibenzylideneacetone)palladium, a naked Pd(0) complex without donating ligand, showed high catalytic activity. A carbon and a silicon substituent are introduced at 1- and 4-positions of the 1,3-dienes regio- and stereoselectively with concomitant decarbonylation of the acid chlorides. A wide variety of allylic silanes are synthesized in high yields from these easily accessible substrates. On the othgr hand, a bulky acid chloride such as adamantane-1-carboxylicacid chloride did not undergo the decarbonylation reaction but afforded allylic silanes containing acyl functionality. In all these reactions, transmetalation of the disilanes with y3-allylchloropalladiumintermediates might be a critical step in the catalytic cycle. As a model reaction for the transmetalation, reaction of di-p-chlorobis[( 1,2,3-y)-4-pheny1-2-butenyl]dipalladium with disilanes was carried out. Although intermediate y3-allylsilylpalladium species could not be detected, the corresponding allylic silanes, silyl chlorides, and Pd(0) metal were formed during the reaction. Furthermore, a similar three-component coupling reaction using aryl iodides, organosilylstannanes, and dienes also proceeded. However, the selectivity and the yield decreased considerably.
Introduction Addition of organosilanes (H-Si) to unsaturated compounds (hydrosilylation)' is a most useful reaction for synthesis of a wide variety of organosilicon compounds [Scheme l(i)]. On the other hand, if a carbon and a silicon unit, instead of a hydrogen and a silicon, are introduced simultaneously into unsaturates (carbosilylation), the reaction might be far more beneficial as synthetic method. However, while some carbonmetal bonds2 such as C-A1 and C-Cu are reactive enough to undergo so-called carbometalation reaction, most C-Si bonds are inert under usual reaction conditions. Therefore, it seems extremely difficult to activate C-Si bonds directly3 toward insertion of unsaturates into these bonds [Scheme l(ii)]. In order to resolve this dilemma, we explored three-component coupling r e a ~ t i o n ,in ~ which a carbon and a silicon substituents are introduced from different sources into unsaturated substrates [Scheme l(iii)]. We adopted 1,3-dienes as the unsaturated substrates, since selective introduction of the carbon and the silicon units at 1- and 4-positions of the 1,3-dienes gives @Abstractpublished in Advance ACS Abstracts, September 1, 1995. (1) Ojima, I. In The Chemistry of Organic Silicon Compounds; Patai, S . , Rappoport, Z., Eds.; John Wiley & Sons: Chichester, 1989; Chapter 25. (b) Collman, J. P.; Hegedus, L. S . ; Norton, J. R.; Finke, R. G. Principles and Applications of Organotransition Metal Chemistry; University Science Books: Mill Valley, CA, 1987; pp 564-568. (2) (a) Negishi, E.-I. Pure Appl. Chem. 1981,53, 2333. (b) Negishi, E.I.; King, A. 0.;Klima, W. L.; Patterson, W.; Silveira, A,, Jr. J. Org. Chem. 1980, 45, 2526. (c) Miller, R. B.; Al-Hassan, M. I. J. Org. Chem. 1985, 50, 2121. (d) Akaki, S.;Imai, A,; Shimizu, K.; Butsugan, Y. Tetrahedron Lett. 1992, 33, 2581. (e) Germon, C.; Alexakis, A.; Normant, J. F. Synthesis 1984, 40 and 43. (3) For direct C-Si bond cleavages within a transition metal coordination sphere, see: (a) Lin, W.; Wilson, S R.; Girolami, G. S . J. Am. Chem. SOC. 1993, 115, 3022. (b) Horton, A. D.; Orpen, A. G. Organometallics 1992, 11, 1193. (c) Chang, L. S.;Johnson, M. P.; Fink, M. J. Organometallics 1991, 10, 1219 and references cited therein. (4) (a) Chatani, N.; Amishiro, N.; Murai, S . J. Am. Chem. SOC. 1991, 113, 7778. (b) Ryu I.; Yamazaki, H.; Kusano, K.; Ogawa, A.; Sonoda, N. J. Am. Chem. SOC. 1991, 113, 8558. (c) White, J. D.;Kawasaki, M. J. Am. Chem. SOC. 1990, 112,4991. (d) Suzuki, M.; Yanagisawa, A.; Noyori, R. J. Am. Chem. SOC. 1988, 110,4718. (e) Tamaru, Y.; Yasui, K.; Takanabe, H.; Tanaka, S . ; Fugami, K. Angew. Chem., Int. Ed. Engl. 1992,31,645. (f) Kosugi, M.; Tamura, H.; Sano, H.; Migita, T. Tetrahedron 1989, 45, 961.
0002-786319511517-9814$09.00/0
Scheme 1 Hydrasilylation
+
H-Slf
>x=Y,
0
-
H-X-Y-Si
f
(9
Carbosilylation (via C-Si cleavage) 0
(ii)
Carbosilylation (via three-component coupling) %x=y:
0
dQ
-
;c-x-v-si:
(iii)
synthetically important allylic silanes. Allylic silanes5are highly versatile synthetic intermediates due to their regioselective reactions with various electrophiles.6 Therefore, much attention has been paid to preparation method7 of allylic silanes including allylic Grignard reactions,'a,b hydrosilylation of 1,3-diene~?-~ and Wittig reactions with'p-silylethylideneph~sphorane.~~*g ( 5 ) (a) Colvin, E. W. Silicon Reagents in Organic Synthesis; Academic: London, 1988; pp 25-37. (b) Weber, W. P. Silicon Reagents for Organic Synthesis; Springer: Berlin, 1983; pp 173-205. (c) Colvin, E. W. Silicon in Organic Synthesis; Buttenvorth: London, 1981; pp 97-124. (6) (a) Sakurai, H. Pure Appl. Chem. 1982,54, 1. (b) Hosomi, A,; Saito, M.; Sakurai, H. Tetrahedron Lett. 1979, 36, 429. (c) Hosomi, A.; Iguchi, H.; Sasaki, J.; Sakurai, H. Tetrahedron Lett. 1982, 23, 551. (d) Koreeda, M.; Ciufolni, M. A. J. Am. Chem. SOC.1982, 104,2308. (e) Armstrong, R. J.; Harris, F. L. Can. J. Chem. 1982, 60, 673. (f) Hoffman, H. M. R.; Henning, R.; Lalko, 0. R. Angew. Chem., Int. Ed. Engl. 1982, 21,442. (g) Fleming, I.; Au-Yeung, B.-W. Tetrahedron Lett. 1982, 37, 13. (h) Pillot, J.-P.; Dunogues, J.; Calas, R. Tetrahedron Lett. 1976, 33, 1871. (7) (a) Sommer, L. H.; Tyler, L. J.; Whitmore, F. C. J. Am. Chem. SOC. 1948, 70,2872. (b) Gilman, H.; Zuech, E. A. J. Am. Chem. SOC. 1959.81, 5925. (c) Tsuji, J.; Hara, M.; Ohno, K. Tetrahedron 1974, 30, 2143. (d) Ojima, I.; Kumagi, M.; Miyazawa, Y. Tetrahedron Lett. 1977, 1385. (e) Ojima, I.; Kumagi, M. J. Organomet. Chem. 1977, 134, C6. (f) Seyferth, D.; Wursthorn, K. R.; Mammarella, R. E. J. Org. Chem. 1977, 42, 3104. (g) Fleming, I.; Paterson, I. Synthesis 1979, 446. (h) Smith, J. G.; Quinn, N. R.; Viswanathan, M. Synth. Commun. 1983, 13, 1. (i) Fleming, I.; Newton, T. W. J. Chem. SOC.,Perkin. Trans. I 1984, 1805. 6) Fleming, I.; Themes, A. P. J. Chem. SOC.,Chem. Commun. 1985.41 1. (k) Trost, B. M.; Yoshida, J.; lautens, M. J. Am. Chem. SOC.1983, 105, 4494.
0 1995 American Chemical Society
1,4-Carbosilylation of 1,j-Dienes
J. Am. Chem. SOC., Vol. 117, No. 39, 1995 9815
In this paper, we describe a palladium catalyzed threecomponent coupling reaction of organodisilanes (Si-Si),8 1,3dienes, and acid chlorides to realize the overall carbosilylation reaction. The reaction is highly regio- and stereoselective providing a useful synthetic method of allylic silanes from these easily accessible starting materials. We also developed similar three-component coupling reaction with 1,3-dienes, where organosilylstannanes (Si-Sn)9 are employed as the silicon source and aryl iodides as the carbon source.
Results and Discussion Carbosilylation of 1,3-Dienes Using Acid Chlorides and Organodisilanes. It is well-known that acid chlorides react with low valent transition metal complexes by oxidative additionlo and generate carbon-transition metal bonds. On the other hand, organodisilaness are very useful silylating reagents in the presence of a transition metal catalyst. First we employed acid chlorides as a carbon source and organodisilanesas a silicon source in the three-component coupling reaction with 1,3-dienes (eq l).'I The results are summarized in Table 1. Benzoyl chloride (la) reacts with hexamethyldisilane (2a) and 1,3butadiene (3a) in the presence of a catalytic amount (5 mol %) of Pd(DBA)2'2-'3(DBA = dibenzylideneacetone) to afford the coupling product (4a) in high yield (entry 1). The phenyl and the silyl substituents are introduced regio- and stereoselectively at the 1- and 4-positions of 3a providing only the ( E ) isomer. Decarbonylation from the acid chlorideI4 proceeded completely and coupling products containing carbonyl functionalities were not detected. '
The reaction also proceeds with substituted benzoyl chlorides in good to high yields. Thus, chloro (IC),bromo (ld), nitro (le), and keto (If and lg) functionalities were tolerated in the (8) Organodisilanes as silylating reagents, see: (a) Obora, Y.; Tsuji, Y.; Kawamura, T. Organometallics 1993, 12, 2853. (b) Obora, Y.; Tsuji, Y.; Kakehi, T.; Kobayashi, M.; Shinkai, Y.; Ebihara, M.; Kawamura, T. J. Chem. SOC.,Perkin Trans. I 1995, 599. (c) Tsuji, Y.; Kajita, S.;Isobe, S.; Funato, M. J. Org. Chem. 1993, 58, 3607. (d) Tsuji, Y.; Lago, R. M.; Tomohiro, S . ; Tsuneishi, H. Organometallics 1992,II,2353. (e) Murakami, M.; Sugimome, M.; Fujimoto, K.; Nakamura, H.; Anderson, P. G.; Ito, Y. J. Am. Chem. SOC. 1993, 115,6487. (f)Ito, Y.; Suginome, M.; Murakami, M. J. Org. Chem. 1991,56, 1948. (g) Yamashita, H.; Catellani, M.; Tanaka, M. Chem. Left. 1991, 241. (h) Sakurai, H.; Eriyama, Y.; Kamiyama, Y.; Nakadaira, Y. J. Organomet. Chem. 1984, 264, 229. (i) Carlson, C. W.; West, R. Organometallics 1983.2, 1801. 6)Watanabe, H.; Kobayashi, M.; Saito, M.; Nagai, Y. J. Organomet. Chem. 1981, 216, 149. (k) Watanabe, H.; Kobayashi, M.; Higuchi, K.; Nagai, Y. J. Organomet. Chem. 1980, 186, 51. (1) Matsumoto, H.; Matsubara, I.; Kato, T.; Shono, K.; Watanabe, H.; Nagai, Y , J. Organomet. Chem. 1980, 199, 43. (m) Matsumoto, H.; Shono, K.; Wada, A.; Matsubara, I.; Watanabe, H.; Nagai, Y. J. Organomet. Chem. 1980, 199, 185. (n) Tamao, K.; Okazaki, S . ; Kumada, M. J. Organomet. Chem. 1978, 146, 87. (0)Tamao, K.; Hayashi, T.; Kumada, M. J. Organomet. Chem. 1976, 114, C19. (p) Sakurai, H.; Kamiyama, Y.; Nakadaira, Y. Chem. Lett. 1975, 887. (4) Sakurai, H.; Kamiyama, Y.; Nakadaira, Y. J. Am. Chem. SOC. 1975, 97, 931. (r) Okinoshima, H.; Yamamoto, K.; Kumada, M. J. Am. Chem. SOC. 1972, 94, 9263.
reaction (entries 3-7). Usually direct synthesis of these functionalized allylic silanes are highly difficult by the conventional proced~res.~ 2- and 1-Naphthoyl chlorides (lh and li) also afforded the corresponding products in excellent yields (entries 8 and 9). 2-Furoyl chloride (lj), 5-bromo-2-furoyl chloride (lk), and 2-thiophenecarbonyl chloride (11) also afforded the (E)-l,Cadducts in good yields (entry 10-12). Terephthaloyl chloride (lm) afforded the corresponding compound having two allylic silane side chains (entry 13). However, o-phthaloyl chloride and 2-@-toluoyl)benzoyl chloride were not consumed in the reaction, suggesting steric congestion with these substrates affects the reaction. Various (E)-alkenoyl chlorides (In-r) can be employed in the present coupling reaction and provided the corresponding (E)- 1,4 adducts regioand stereoselectively (entries 14- 18). Alkynoyl chlorides (1s and It) also afforded the corresponding products in high yields (entries 19 and 20). As 1,3-dienes, isoprene (3b) and 2,3dimethyl-1,3-diene (3c) can be employed. The reaction gave the products (4u-w) regioselectively (entries 21 -23); with isoprene (3b) the trimethylsilyl group is introduced on the methylene carbon closer to the methyl substituent. In these cases, however, stereoselectivity was often modest. Symmetrically substituted disilanes such as 1,l'-diphenyl- (2b), 1,l'di-(4-fluorophenyl)- (2c), 1,l'-dichloro- (M), and 1,l'-difluorotetramethyldisilanes (2e) afforded the corresponding carbosilylation products (4x-a) with high regio- and stereoselectivity (entries 24-27). As for monosubstituted unsymmetrical disilanes, phenylpentamethyldisilane (20 afforded the dimethylphenylsilyl derivative (4x) exclusively (entry 28), whereas fluoropentamethyldisilane(2g) gave fluorodimethyl isomer (4a) as a major product (entry 29). Effects of some reaction conditions and selected catalyst precursors were examined in the coupling reaction using la, 2a, and 3a. As a solvent, aromatic hydrocarbon such as toluene gave the best results (entry 1); the reaction in tetrahydrofuran (THF) and dimethylfomamide (DMF)lowered the yields considerably (15% and 5%, respectively). The reaction proceeds smoothly at 80 "C, while lower (50 "C) or higher (130 "C) reaction temperature reduced the yield considerably (19% and 36%, respectively). As a catalyst precursor, Pd(DBA)2,I2.l3a naked Pd(0) complex without donating ligand, is most effective. An addition of AsPh3 (AsPd = 4) or P(0Et)s (PPd = 4) to Pd(DBA)2 reduced the yield of 4a to 41% or 13%, respectively. (9) Organosilylstannanes as silylating and/or stannylating reagents, see: (a) Tsuji, Y.; Obora, Y. J. Am. Chem. SOC. 1991, 113,9368. (b) Obora, Y.; Tsuji, Y.; Asayama, M.; Kawamura, T. Organometallics 1993, 12, 4697. (c) Murakami, M.; Morita, Y.; Ito, Y. J. Chem. SOC., Chem. Commun. 1990, 428. (d) Mitchell, T. N.; Wickenkamp, R.; Amamria, A.; Dicke, R.; Schneider, U. J. Org. Chem. 1987, 52, 4868. (e) Chenard, B. L.; Van Zyl, C. M. J. Org. Chem. 1986,51,3561. (f) Mitchell, T. N.; Killing, H.; Dicke, R.; Wickenkamp, R. J. Chem. SOC.,Chem. Commun. 1985,354. (9) Chenard, B. L.; Laganis, E. D.; Davidson, F.; RajanBabu, T. V. J. Org. Chem. 1985, 50, 3666. (10) Deeming, A. J.; Shaw, B. L. J. Chem. SOC.(A) 1969,597. (b) Ilmaier, B.; Nyholm, R. S. Natunvissenschafren 1969, 56, 636. (c) Dolcetti, G.; Hoffman, N. W.; Collman, J. P. lnorg. Chim. Acta 1972, 6, 531. (1 1) For a preliminary account of a portion of this work, see: Obora, Y.; Tsuji, Y.; Kawamura, T. J. Am. Chem. SOC. 1993, 115, 10414. (12) (a) Takahashi, Y.; Ito, T.; Sakai, S.;Ishii, Y. J. Chem. Soc., Chem. Commun. 1970, 1065. (b) Rettig, M. F.; Maitlis, P. M. Inorg. Synth. 1977, 17, 134. (13) (a)Pd2(DBA)yCHC1313bshowed similar catalytic activity. (b) Ukai, T.; Kawazuka, H.; Ishii, Y.; Bonnet, J. J.; Ibers, J. A. J. Organomet. Chem. 1974, 65, 253. (14)Tsuji, J.; Ohno, K. J. Am. Chem. SOC. 1966, 88, 3452. (b) Ohno, K.; Tsuji, J. J. Am. Chem. SOC. 1968, 90, 99. (c) Egglestone, D. L.; Baird, M. C.; Lock, J. C.; Turner, G. J. Chem. Soc., Dalton Trans. 1977, 1576. (d) Stille, J. K.; Fries, R. W. J. .4m. Chem. Soc. 1974, 96, 1514. (e) Lau, K. S. Y.; Becker, Y.; Huang, F.; Baenzigen, N.; Stille, J. K. J. Am. Chem. SOC. 1977, 99, 5664. (f) Roberto, D.; Alper, H. Organometallics 1984, 3, 1767. (g) Foglia, T. A.; Barr, P. A.; Idacavage, M. J. J. Org. Chem. 1976, 41, 3452.
Obora et al.
9816 J. Am. Chem. Soc., Vol. 117, No. 39, 1995 Table 1. 1,4-Carbosilylation of 1,3-Dienes Using Acid Chlorides and Organodisilanes" entry
acidchlonde
disilrne
2.
diene
3.
enW
prC4UCt
actdchloride
dlsllane
diene
2.
3s
"L.,, 4b
77
yield/4bb
prodvct
-uYl,
72
op
Conditions: acid chloride (1: 0.50 mmol), disilane (2: 0.50 mmol), 1,3-diene (3: 1.5 mmol), Pd(DBA)z (0.025 mmol; 5 mol %), and toluene (2.0 mL) at 80 "C for 4 h. Isolated yields. Numbers in parentheses show GC yields determined by the internal standard method. The disilane (1.0 mmol). E/Z = 75/25. e E/Z = 91/9. f EIZ = 65/35.
Furthermore, the addition of PBu3 (PPd = 4) or bidentate ligands such as DPPE [ 1,2-bis(diphenylphosphino)ethane], DPPP [ 1,2-bis(diphenylphosphino)propane], and DPPF [ 1,l'bis(diphenylphosphino)ferrocene] (for these bidentate phosphines, ligandPd = 2) totally suppressed the conversion of la. Other selected transition metal precursors (5 mol %) such as Pd(PPh3)4, PdC12(PPh3)2, Pt(DBA)2, and Pt(C0)2(PPh3)2 were not active as the catalyst and the acid chlorides remained intact. Thus, palladium(0) complex without coordinating ligands is essential as the catalyst precursor for the present threecomponent coupling reaction. In the reactions listed in Table 1, the de~arbonylationl~.'~ from the acid chlorides (1) took place completely. Usually, catalytic decarbonylation of acid chlorides or aldehydes are sluggish,I6 especially at lower reaction temperatures. In the present coupling reaction, highly unsaturated nature of the palladium catalyst center might facilitate such fast and complete decarbonylation of the acid chlorides. After the reaction, comparable amount of carbon monoxide was detected in the gas phase by GC analysis (on Molecular Sieve 13X-S, oven temperature at 50 "C). When the reaction was carried out under carbon monoxide pressure (10 kg/cm2), consumption of the acid chlorides was low (
