Alternative method of Boc-removal from sulfamide using silica-phenyl sulfonic acid in conjunction with microwave heating.

A general method was used to prepare an array of unsymmetric sulfamides. This was accomplished by the stepwise addition of CSI to tert-butanol followed by the addition of amines. To increase diversity, nitrogen group of Boc-sulfamides was alkylated with alcohols using Mitsunobu reaction and Boc-group was removed using Si-TsOH. Microwave heating was used in all the steps. The final sulfamides were released from Si-TsOH using NH3 in MeOH.