Process for the preparation of 1-(2,6,6-trimethyl-2-cyclohexene-1-yl)-but-2-ene-1-one

A process for the preparation of α-Damascone [1-(2,6,6-trimethyl-2-cyclohexene-1-yl)-2-buten-1-one] represented by formula (II)

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• said process comprising the steps of:
• (a) adding 2,6,6-trimethyl-1-cyclohexene over a period of 30-95 minutes to a refluxing mixture of an hydrocarbon solvent, Lewis acid and Crotonic anhydride at a temperature in the range of 60-120° C.;
• (b) cooling the reaction mixture of step (a) to an ambient temperature of 25-30° C.;
• (c) pouring the cooled reaction mixture of step (b) into aqueous alkali carbonate solution and stirring the reaction mixture for about 5-20 minutes;
• (d) separating the organic layer and washing the organic layer of step (c) with water till the washing becomes neutral;
• (e) drying and removing organic solvent from the organic layer to obtain crude product and purifying the crude product to obtain pure α-Damascone of formula (II).