Wittig reactions of a bis-triphenylphosphonium pyridoxine derivative

Wittig reactions of a bis-triphenylphosphonium pyridoxine derivative with five aromatic and aliphatic aldehydes led to a series of mono- and bis-alkenyl substituted products. The reactions also demonstrated unusual reactivity patterns leading to unexpected products, including a Z-shaped hyperconjugated structure with trans-configuration for all three alkene fragments, and a tricyclic 9,10-dihydro-1H-[1,3]dioxino[4,5-c]quinoline formed as a result of non-symmetric Wittig olefination followed by a rare type of intramolecular cyclization. The obtained products represent prospective biologically active agents, while one compound is a potential microenvironment- and interaction-sensitive molecular probe.