Regioselective synthesis of highly substituted enol esters from ketoketene dimer β-lactones
作者:Eric C Salo、Kyle R Dayak、Jacob Huxford、Pei-Hsun Wei、Nicholas J Peraino、Nessan Joseph Kerrigan
DOI:10.3998/ark.5550190.p008.443
日期:——
A method for the regioselectivesynthesis of highlysubstitutedenolestersfromketoketenedimersβ-lactones is described. Methylphenylketene dimer was subjected to a sequential one-pot reaction sequence involving ring-opening with an organolithium to give an enolate intermediate, followed by enolate acylation with an acyl chloride to give a highlysubstitutedenolester as the final product. Complete
作者:Ahmad A. Ibrahim、Gero D. Harzmann、Nessan J. Kerrigan
DOI:10.1021/jo8024785
日期:2009.2.20
A general method for the catalytic dimerization of ketoketenes is described. Tri-n-butylphosphine was found to be the optimal organocatalyst for the racemic reaction. When lithium iodide was used as an additive, the reaction was rendered selective for dimer formation (dimer/trimer >= 16:1). Ring-opening reactions of the ketoketene dimers as well as preliminary studies toward the development of an asymmetric variant are also reported.