Palladium catalyst-mediated decarboxylation of two allylic esters of arene carboxylic acids, towards the synthesis of 3,4-dialkoxythiophenes

Abstract:

Two model molecules, allyl 2,6-dimethoxybenzoate (1) and 2,5-dicarballyloxy-3,4-ethylendioxy-thiophene (2a), were syn-thesized. These were subjected to the same conditions as the decarboxylation of allyl-Β-ketoesters mediated by Pd0 catalyst. The CO2 elimination for 1 was possible only when a second catalyst of PdII was added. Under these conditions a homocoupling product (3) was possible. An electrophilic PdII species seems to be necessary to generate the decarboxylated products, but this requires a long reaction time and the yields are moderated.

Año de publicación:

2018

Keywords:

• Arene
• Allyl ester
• Biaryl
• Decarboxylation
• Pd catalyst
• Aalkoxythiophene

Fuente:

scopus