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چکیده
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The catalytic generation of carbanions and their use in carbon-carbon bond forming reactions is currently a major interest. ,a-Unsaturated ketones, called chalcones (1,3- diphenyl-2-propen-1-one) are derived from the Claisen–Schmidt condensation between acetophenones and benzaldehydes. Chalcones are key precursors in the synthesis of various flovonoids and followed by flavanones, and have several interesting biological activity. Traditional method consists of condensation at 50 oC using alkaline hydroxide or sodium ethoxide over a period of 12-15 h. Several bases have been used. We report a mild and simple method for the generation of enolates from acetophenone and synthesis of chalcones using catalytic amount of cesium carbonate as a weak base via dual activation in EtOH 95% at room temperature with excellent yields and selectivity.
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