Abstract: Objective To investigated the reaction situation of quaternary ammonium salts with base.Methods Atropine reacted with bromoacetonitrile to give N-cyanomethyl-atropine bromide which was treated with sodium borohydride.In order to simplify the study,hydrolysis of atropine afforded tropine.Oxidation of tropine with chromic oxide gave tropinone which can be quaternized to 5 in quantitative yield.Quaternary ammonium salts 5 was treated with NaH.Results N-cyanomethyl-atropine bromide was treated with sodium borohydride to give 3 and 4.Reaction of N-cyanomethyl-tropinone bromide with sodium borohydride leads to 7.Conclusion Atropine derivatives react with sodium borohydride to performed Hofmann elimination reaction and cyclize to produce 7.

Key words: naturally occurring alkaloid, tropinone, quaternary ammonium salts