Synthesis of π-Conjugated Molecules Based on 3,4-Dioxypyrroles <i>via</i> Pd-Mediated Decarboxylative Cross-Coupling
作者:Frank A. Arroyave、John R. Reynolds
DOI:10.1021/jo201770j
日期:2011.11.4
A general scheme for the synthesis of pi-conjugated molecules based on 3,4-dioxypyrroles is presented. The pi-conjugated molecules were synthesized via Pd-mediated decarboxylative cross-coupling using various 3,4-propylenedioxypyrrole carboxylic acids and aryl bromides, including the base-sensitive electron acceptor 4,7-dibromobenzo[c][1,2,5]-thiadiazole (BTD). N-Methylpyrrolidone was used as solvent, Pd(acac)(2) was employed as the palladium source and P(o-tol)(3) as the ligand. The methodology was applied to 3,4-dioxypyrrole monoacids and 3,4-dioxypyrrole diacids to produce multi-ring pi-conjugated systems containing phenyl, thiophenyl, BTD, and pyridinyl units. In general, the method has yielded a practical approach for the synthesis of 3,4-dioxypyrrole-based pi-conjugated molecules in acceptable to high yields of 44-94%.