Reaction of 4-(N, N-Dimethylamino)-2-phenyl-2-(2-pyridyl)butanenitrile and Related Compounds with Ethyl Chloroformate; Formation of Indolizinium and Quinolizinium Chlorides

Abstract

4-(N, N-Dialkylamino)-2-phenyl-2-(2-pyridyl)butanenitriles (10, 11 and 12) and 5-(N, N-dimethylamino)-2-phenyl-2-(2-pyridyl)pentanenitrile (13) react with ethyl chloroformate, via a cyclization-N-dealkylation process, to give indolizinium and quinolizinium salts (1 and 2). Compounds 1 and 2 are also obtained by reaction of the alcohol derivatives 14 and 15 with thionyl chloride. Reaction of 2-phenyl-2-(2-pyridyl)ethanenitrile (9) in the presence of potassium hydroxide in dimethyl sulfoxide, leading to [2-hydroxy-2-phenyl-2-(2-pyridyl)ethyl]methylsulfoxide (21), is also described.