Nickel-catalyzed ring-opening hydroacylation of methylenecyclopropanes: synthesis of gamma,delta-unsaturated ketones from aldehydes.
A nickel-catalyzed intermolecular hydroacylation of methylenecyclopropanes (MCPs) has been developed. The reaction proceeds with stereospecific cleavage of the proximal C-C bond of the cyclopropane ring to give gamma,delta-unsaturated ketones with high diastereoselectivities. A nickel catalyst generated in situ from Ni(cod)(2) and P(n-Bu)(3) with a P/Ni ratio of 1:1 is effective for the hydroacylation, in which benzaldehyde derivatives, heteroaryl aldehydes, and aliphatic aldehydes react with MCPs at 60-100 degrees C to afford the corresponding ketones in high yields.
Taniguchi
Hiroki
H
Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Kyoto 615-8510, Japan.
Ohmura
Toshimichi
T
Suginome
Michinori
M