A convenient procedure for smooth palladium-catalyzed allylic alkylation by sodium dimethyl malonate and cyclopentadienide. A new synthesis of allylic substituted cyclopentadienes.
作者:J.C. Fiaud、J.L. Malleron
DOI:10.1016/s0040-4039(00)92193-2
日期:——
The use of the Pd(dba)12/dpe catalytic system in allylic alkylation allows sodium dimethyl malonate to react with allylicacetates at room temperature. According to this procedure, a novel synthesis of allylicsubstituted cyclopentadienes is described through the use of cyclopentadienide anion as a nucleophile.
N-Phenyldiethanolamine (1f) is an efficient ligand for zinc-catalyzed transesterification of alcohols with vinyl acetate (R3 = Me) at room temperature. In the case of using other vinyl esters (R3 = Et, n-Pr, Ph), the corresponding products were easily obtained in the presence of pyridine-type ligand 2 instead of aminoalcohol 1f.
Various mono- and di-substituted cyclopentadienes have been prepared by palladium-catalyzed alkylation of allylic esters with cyclopentadienide and t-butyl-cyclopentadienide anions. The same procedure has been applied to the preparation of substituted indenes.