Silylative Cyclocarbonylation of 1,6-Diynes and 1,6-Enynes

We have explored two types of carbon-carbon bond forming reactions operated under almost neutral conditions. Both reactions are initiated by the formation of an H-Rh-Si species through oxidative addition of a hydrosilane to a low-valence rhodium complex. Aldol-type three-component couphngs are followed by the insertion of an a,yS-unsatu-rated carbonyl compound into a Rh-H bond, whereas silylformylation is accomplished by the insertion of an acetylenic moiety into a Rh-Si bond. 

347 This finding stimulated Bergman and Heathcock to isolate Rh-enolate complexes (d) Slough, G.A. Bergman, R. G. Heathcock, C.H. J. Am. Chem. Soc. 1989, 111, 938. 

RhCl3 3H20 and Co(dpm)2 are used for the similar coupling of a,/ -enoates, however, neither is effective for the reaction of a,/3-enones (b) Revis, A. Hilty, T. K. Tetrahedron Lett. 1987, 28, 4809 (c) Isayama, S. Mukaiyama, T. Chem. Lett. 1989, 2005  

Nagashima, H. Tetrahedron Lett. 1991, 32, 7431 (d) Matsuda, I. Tsuchihashi, T Takeuchi, K. Sobue, H. unpublished results (e) Matsuda, I. Takeuchi, K.  

Modem Rhodium-Catalyzed Organic Reactions. Edited by P. Andrew Evans Copyright 2005 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 3-527-30683-8 

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