Metal and Activating Group Free C-4 Alkylation of Isoquinolines via a Temporary Dearomatization Strategy
作者:Aaron J. Day、Timothy C. Jenkins、Marvin Kischkewitz、Kirsten E. Christensen、Darren L. Poole、Timothy J. Donohoe
DOI:10.1021/acs.orglett.2c04149
日期:2023.2.3
A simple method for the C-4alkylation of isoquinolines is described using benzoic acid as a nucleophilic reagent and vinyl ketones as an electrophile. The reaction shows tolerance for substitution at C-3, and C-5–C-8 positions as well as allowing some variation of the vinyl ketone electrophiles. The products contain a carbonyl that can act as a synthetic handle for further manipulations giving esters
of aryl bromides with primary and secondaryallylicalcohols, performed in the presence of an air-stable phosphinito complex of palladium(II), produced the corresponding carbonylcompounds. Reactions with tertiary allylicalcohols under the same conditions generated the aromatic conjugated alcohols. allylicalcohols - Heck reaction - palladium - aldehydes - ketones