Synthesis of Pyridines and Pyrido[2,3-d]pyrimidines by the Lewis Acid Catalysed Bohlmann-Rahtz Heteroannulation Reaction
作者:Mark C. Bagley、James W. Dale、David D. Hughes、Maren Ohnesorge、Nathan G. Phillips、Justin Bower
DOI:10.1055/s-2001-17447
日期:——
Lewis acids catalyse the Bohlmann-Rahtz heteroannulation reaction to generate highly functionalised pyridines from enamino esters and alkynones in a single synthetic step. Of the catalysts studied, ytterbium(III)trifluoromethanesulfonate and zinc(II) bromide are the two most efficient for the synthesis of pyridines and pyrido[2,3-d]pyrimidines, from ethyl β-aminocrotonate or 2,6-diaminopyrimidin-4-one respectively, in up to 94% yield.