Synthesis of 3-phosphorylated 2-aza-1,3-dienes from imines derived from bisphosphonates

Article abstract of DOI:10.1016/S0040-4039(99)00116-1

A synthesis of 2-aza-1,3-butadienes 3 substituted with a phosphonate group in the 3-position is described. The key step is the olefination reaction of bisphosphonylalkyl imino compounds 2, with aldehydes in the presence of base. Heterocyclisation of 2-azatrienes 5 afforded substituted 2- phosphorylated pyridines 6.