Halogen catalyzed acetylenic oxy-cope rearrangement in N-methyl-2-pyrrolidone solvent a new industrial process for pseudoionone and its analogues

Article abstract of DOI:10.1016/S0040-4039(00)74572-2

Selective synthesis of pseudoionone was achieved by the acetylenic oxy-Cope rearrangement of 4-isopropenyl-3,7-dimethyl-6-octen-1-yn-3-ol (3) in N-methyl-2-pyrrolidone solvent containing a trace of hydrochloric acid, hydrobromic acid, iodine, ammonium bromide and ammonium chloride catalysts.