Catalytic asymmetric reactions for organic synthesis: the combined C-H activation/siloxy-cope rearrangement.

Tetrakis(N-[4-dodecylbenzenesulfonyl]-(L)-prolinate) dirhodium [Rh(2)(S-DOSP)(4)]-catalyzed decomposition of vinyldiazoacetates in the presence of allyl silyl ethers results in the formation of the direct C-H insertion product and the product derived from a combined C-H activation/siloxy-Cope rearrangement. Both products are formed with very high diastereoselectivity (>94% de) and high enantioselectvity (78-93% ee). Under thermal or microwave conditions, the direct C-H insertion product undergoes a siloxy-Cope rearrangement in a stereoselective manner.