Aza-Wittig reaction of fluoroalkylated N-vinylic phosphazenes with carbonyl compounds. Usefulness of 2-azadienes for the preparation of fluoroalkyl pyridine derivatives

A method for the preparation of 3-fluoroalkyl substituted 2-aza-butadienes by aza-Wittig reaction of 3-fluoroalkyl-N-vinylic phosphazenes and aldehydes is reported. [4+2] Cycloaddition reaction of these heterodienes with enamines gives fluoroalkyl substituted pyridine , , and isoquinoline , derivatives.