Reaction of Arylglyoxals with 2-Amino Heterocycles

Article abstract of DOI:10.1021/jo00285a024

The reaction of some arylglyoxals with a variety of 2-amino heterocycles, including pyridine, diazine, and azole derivatives, has been studied, with or without BF3*Et2O complex as catalyst.On the basis of the isolation of different intermediate carbinolamines and of some crossover cyclization experiments, a reasonable mechanism has been proposed for all these processes.In addition, some structural features of the resulting bicyclic imidazo<1,2-a> derivatives having a potential hydroxyl group in position 3 are discussed.