First examples of 2,6-diarylnicotinaldehydes prepared under conventional and microwave conditions

Enaminoketones undergo unexpected self condensation in acetic acid to produce a wide range of 2,3,6-trisubstituted pyridine derivatives in excellent yields in the presence of NH4OAc. This is the first Letter on the synthesis of 2,6-diarylnicotinaldehydes. The reaction was studied under microwave irradiation and conventional heating. However, mixed condensations were observed when two different enaminones are combined. (C) 2015 Published by Elsevier Ltd.