Dakin-West trick in the design of novel 2-alkyl(aralkyl) derivatives of oxazolo[3,2-a]pyridines.
A series of previously unavailable derivatives of 2-alkyl- and 2-benzylderivatives of oxazolo[3,2-a]pyridines III were obtained via tandem ring opening and ring closure from stable mesoionic 3-acyloxazolo[3,2-a]pyridinium-2-olates I. The key intermediates of this tandem transformation are N-(b-oxoethyl)pyridones-2 II obtained by Dakin-West acylation of (pyridone-2-yl-1)acetic acid. An example of further utilization of this strategy is illustrated by preparation of unknown 2-benzylimidazo[1,2-a]pyridine from the salt I and ammonia.
Kazhkenov
Zeinul-Gabiden M
ZG
Chemistry Department, Moscow State University, Moscow 119992, Russia.
Bush
Alexander A
AA
Babaev
Eugene V
EV
D000215:Acylation; D000641:Ammonia / Q000737:chemistry; D006868:Hydrolysis; D008956:Models, Chemical; D010081:Oxazolone / Q000737:chemistry; D010472:Perchlorates / Q000138:chemical synthesis / Q000737:chemistry; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry; D011728:Pyridones / Q000737:chemistry; D012492:Salts
D010472:Perchlorates; D011725:Pyridines; D011728:Pyridones; D012492:Salts; D010081:Oxazolone; D000641:Ammonia