Asymmetric Ion Pair Catalysis of 6π Electrocyclizations: Brønsted Acid Catalyzed Enantioselective Synthesis of Optically Active 1,4‐Dihydropyridazines

Abstract

Electric slide: Described is a general, operationally simple, highly enantioselective Brønsted acid catalyzed condensation/6π-electrocyclization reaction between hydrazones and α,β-unsaturated aldehydes that yields valuable 1,4-dihydropyridazines. The reaction exhibits high tolerance towards functional groups and affords products with up to 98 % ee.