method for manufacture of gamma, delta - unsaturated ketones by carroll reaction in cyclic as or gamma lactonen as solvent

摘要

Preparation of gamma , delta -unsaturated ketones (III) comprises: (a) reaction of vinyl carbinols or propargyl alcohols with acetoacetic acid alkyl esters or diketenes; and (b) thermal rearrangement of the resultant acetoacetate optionally in the presence of an aluminium catalyst to give (III) via the Carroll reaction. Reaction step (a) or (b) is conducted with a cyclic carbonate of formula (I) or gamma -lactone of formula (II) as solvent: R1-R3 =H, Me, or Et; and R4 = H, Me, Et, i-Pr, phenyl or methoxymethyl.