2,3-Diarylquinoxaline directed mono ortho-aroylation via cross-dehydrogenative coupling using aromatic aldehydes or alkylbenzenes as aroyl surrogate
作者:Sourav Kumar Santra、Arghya Banerjee、Bhisma K. Patel
DOI:10.1016/j.tet.2014.02.034
日期:2014.4
directed mono ortho-aroylation protocol has been developed using aromaticaldehydes or alkybenzenes as aroyl surrogates. Out of the four available ortho sp2 C–H bonds in the two aryl rings of 2,3-diarylquinoxaline one of the C–H bond is selectively ortho-aroylated. The reaction proceeds via the aroyl radical path in the case of aromaticaldehydes while the alkylbenzenes follow either an aroyl radical or a
Pd(<scp>ii</scp>)-catalysed o-aroylation of directing arenes using terminal aryl alkenes and alkynes
作者:Nilufa Khatun、Arghya Banerjee、Sourav K. Santra、Ahalya Behera、Bhisma K. Patel
DOI:10.1039/c4ra11014e
日期:——
A substrate-directed Pd-catalysed o-aroylation strategy has been demonstrated using new aroyl surrogates viz. terminal aryl alkenes and alkynes in the presence of TBHP. By a subtle change in catalyst from Cu to Pd, a differential selectivity is observed. While terminal aryl alkenes/alkynes in the presence of Cu/TBHP are reported to act as o-aryloxy (ArCOO–) sources, the use of Pd/TBHP installs an aroyl (ArCO–) group at the ortho position with respect to the directing arenes.