Novel conversion of 4-aminoquinolines to new tricyclic (R,S)-3-methylazeto[3,2-c] quinolin-2(2aH)-ones and versatile one step synthesis of N-(quinolin-4-yl) carbamates from 4-aminoquinolines

Reaction of 4-aminoquinolines with 4-nitrophenyl chloroformate have resulted in finding a novel transformation of 4-aminoquinolines to tricyclic (R,S)-3-methylazeto[3,2-c]quinolin-2(2aH)-ones. The structure of azeto-quinolinone was determined via spectroscopic and chemical methods. Various alcohols were used as nucleophiles to open the 1-azetinone ring to give the corresponding N-(quinolin-4-yl)carbamates in good yields. We also found a new and versatile one step synthesis of N-(quinolin-4-yl)carbamates by reacting 4-aminoquinolines with alkyl chloroformates in the presence of anhyd K2CO3 in acetonitrile.