Hydroxylamine-O-sulfonic acid: As a dual role reagent

Ramachandran and co-workers reported regioselective hydroboration-amination of fluoro-substituted styrenes with BH2I.SMe2 and hydroxylamine-O-sulfonic acid respectively. After hydroboration of 4-fluorostyrene, the reaction mixture was cooled to 0°C, quenched with methanol and aminated using hydroxylamine-O-sulfonic acid to obtain a 72% yield of essentially pure primary amine (ratio of a:b= 97:3). Similarly, the hydroboration-amination of 3-trifluoromethyl styrene gave a 65% yield of primarily the primary amine (ratio of a:b = 92:8)