Lactone Chemistry. Synthesis of β-Substituted, γ-Functionalized Butanolides and Butenolides and Succinaldehydic Acids from Glyoxylic Acid

Article abstract of DOI:10.1021/jo00337a013

The Mannich-type aminoalkylation reaction of enolizable aldehydes with morpholine and glyoxylic acid instead of formaldehyde was investigated: in basic and neutral media were obtained α,γ-dimorpholinobutanolides 2 and α-morpholino-γ-hydroxybutanolides 1, respectively.In acidic medium the spontaneous elimination of the α-morpholino group afforded the γ-hydroxybutenolide 8.The reaction pathways were suggested from the isolation and characterization of some intermediates of the Mannich reaction.These lactone structures constitute versatile synthetic intermediates for the preparation of β-substituted succinaldehydic acids 15 and 5-substituted 3-(2H)-pyridazinones 13 and 14.