Zinc-mediated C-C bond sigmatropic rearrangement: a new and efficient methodology for the synthesis of beta-diketones.
A new and efficient methodology has been developed for the synthesis of beta-diketones from aromatic alpha-bromo ketones in the presence of Furukawa reagent under mild conditions. The present transformation is proposed to proceed via a Reformatsky-type reaction of alpha-bromo ketones, followed by C-C bond sigmatropic rearrangement of the aldolate intermediate to give beta-diketones in moderate to good isolated yields, while aliphatic alpha-bromomethyl ketones resulted in the formation of 2,4-disubstituted furans or cis-1,2-disubstituted cyclopropanols in moderate yields. The scope of this process was investigated, and a tentative mechanism was proposed.
Li
Lezhen
L
Department of Applied Chemistry, Tianjin University of Technology, Tianjin 300191, P.R. China.
Cai
Peijie
P
Xu
Da
D
Guo
Qingxiang
Q
Xue
Song
S