Sulfonamides of primary amines bearing an aromatic ring at the gamma-position were treated with (diacyloxyiodo)arenes and:iodine under irradiation conditions with;a tungsten-lamp to give the corresponding 1,2,3,4-tetrahydroquinoline derivatives in moderate to good yields. Here, the reactivity depends on the Z-group (protecting group) of the starting amides. Under the same reaction conditions, some sulfonamides were treated with (diacetoxyiodo)benzene and iodine in the presence of aromatics to give the corresponding N-arylated amides. These reactions proceed through the intramolecular and intermolecular amidations onto aromatic rings via the sulfonamidyl radicals formed.
Highly specific N-monomethylation of primary aromatic amines
作者:Adolfo Le Pera、Antonella Leggio、Angelo Liguori
DOI:10.1016/j.tet.2006.03.104
日期:2006.6
A synthetic methodology for the specific conversion of primary aromatic amines into their N-monomethyl derivatives under very mild conditions is presented. Anilines are treated with 4-nitrobenzenesulfonyl (nosyl) chloride to generate the corresponding sulfonamides 2 in high yields. The subsequent N-methylation reaction of the sulfonamides 2 with a solution of diazomethane is rapid and quantitative