Non-nucleophilic base (KHMDS) mediated nucleophilic conversion of Merrifield resin into aminomethyl resin

During a series of alkylation reactions on Merrifield resin involving a number of alkoxides, generated in situ by the treatment of alcohols with a variety of bases (NaH, LiHMDS, etc.), it was determined that treatment of the resin with a number of hexamethyldisilazide bases gave rise to high yields of aminomethyl resin, presumably by nucleophilic displacement of the chloride. The reaction was optimised as a simple one-step process for the generation of aminomethyl resin from chloromethyl polystyrene. The resulting resin was used to synthesise a tripeptide.