A novel one-pot three-steps process has been developed, including phosphine-catalyzed
Rauhut–Currier reaction of γ-alkyl allenoates, Diels–Alder reaction with di-tert-butyl azodicarboxylate, followed by deprotection of Boc group to prepare tetra-substituted
1,6-dihydropyridazines in good yields. The 1,6-dihydropyridazines were easily converted
to pyridazine derivatives via oxidative aromatization by DDQ.
Key word
dihydropyridazine - pyridazine - Rauhut–Currier - Diels–Alder - one pot - phosphine
