Triazolopyridines. 16 1. lithiation of 3-cyano[1,2,3]triazolo[1,5-a]-pyridine
摘要:
Various methods for the synthesis of 3-cyanotriazolopyridine 8 by diazo transfer to 2-pyridylacetonitrile are described. Lithiation of the triazolopyridine 8 using LDA or TMPA followed by quenching with TMS chloride, gave the 4-mono-, the 7-mono-,and the 4,7- di TMS derivatives 14, 18, and 15, and the amidines 16 and 17, in contrast to the previously reported regiospecific attack at position 7. A Grignard reaction on compound 8 gave 3-propionyl triazolopyridine, 13.