J. Org. Chem. 1993,58, 4187-4188
4187
Rhodium-Catalyzed Ringopening Silylformylation of Epoxides Leading to &Siloxy Aldehydes Yoshiya Fukumoto, Naoto Chatani, and Shinji Murai' Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565, Japan Received April 26, 1993
Summary: In the presence of [RhCl(C0)212and 1-methylpyrazole,the reaction of epoxides with a hydrosilane and carbon monoxide resulted in ring-opening silylformylation leading to 0-siloxy aldehydes. The carbonylativering opening of epoxides has been of long-standing interest not only because of ita synthetic potential but also because of the related interest in homogeneous catalysis.' Ring-opening esterifications,2 carboxylations: aminocarbonylations,4and formylations6 of epoxides of varying efficiencieshave been reported. In 1977,we reported that the CoZ(CO)a-catalyzedreaction of epoxides with a hydrosilane and carbon monoxide resulted in ring-opening silylformylationseyielding 0-siloxy aldehydes.7 In this reaction, however, the desire to prevent the product aldehydesfrom undergoing further reactions, such as formylations,8hydrwilylations? and dehydrogenative silylations,1° required us to use excess amounts of the starting epoxides. We now wish to report that the use of Rh-amine catalysts enables the conversion of epoxides to 0-siloxyaldehydeswithout causing further reactions of the product aldehydes.ll Early in this study, we carried out the reaction of cyclohexene oxide (1) (2.5 mmol) with HSiEhMe (7.5 mmol) and CO (50 atm initial pressure at 25 "C) in the in CeHe (5 mL) at presence of [RhCl(C0)212(0.1 "01) 100"C for 20 h. Only cyclohexanolsilyletherwas obtained ~~
~
Table I. Rhodium-Catalyzed Bing-Omning Silylformylation of Epoxidm with HSiM@h and CO. entry
hydrosilane and carbon monoxide hm been recently reported. Matsuda, I.; Ogieo, A.; Sato, S.; Izumi, Y. J. Am. Chem. SOC.1989,111,2332. Ojima, I.; Ingallina, P.; Donovan, R. J. Clos, N. Organometallics 1991, 10, 38. Doyle, M. P.; Shanklii, M.S. Organometallics 1993,12,11. Wright, M. E.;Cochran, B. B.J. Am. Chem. SOC.1993,115, 2059. (7) Seki,Y.: Murai, S.; Yamamoto, I.; Sonoda, N. Angew. Chem., Int. Ed. Engl. 1977, 16, 789. (8) Murai, 5.;Kato, T.; Sonoda, N.; Seki, Y.; Kawamoto, K. Angew. Chem., Int. Ed. Engl. 1979,18, 393. (9) Ojima, I. In The Chemiatry of Organic Silicon Compounds;Patai, S., Rappoport, Z.,Eds.; John Wiley & Sone: New York, 1989; Part 2, pp
147s1526. (10) Seki, Y.; Murai, S.; Sonoda, N. Angew. Chem., Int. Ed. Engl. 1978,17,199. (11) For our recent results on the transition metal-catalyzed reaction with hydrosilanes and carbon monoxide, see: Chatani, N.; Ikeda, S.; Ohe, K.; Murai,S. J. Am. Chem. SOC.1992,114,9710. Ikeda, S.; Chatani, N.; Murai, S. Organometallics 1992,11,3494. Ikeda,S.;Chatani,N.; KajiLawa, Y.; Ohe, K.; Murai,S. J . Org. Chem. 1992,57, 2.
yield," %
product
82 1
66
72
3
4c
/\
