2-NITROBENZENESULFONAMIDES AND 4-NITROBENZENESULFONAMIDES - EXCEPTIONALLY VERSATILE MEANS FOR PREPARATION OF SECONDARY-AMINES AND PROTECTION OF AMINES

2- and 4-Nitrobenzenesulfonamides, readily prepared from primary amine s, undergo smooth alkylation by Mitsunobu reaction or by conventional methods to give N-alkylated sulfonamides in near quantitative yields. These sulfonamides could be deprotected readily via Meisenheimer compl exes upon treatment with thiolates in DMF at room temperature, giving secondary amines in high yields.