α, β unsaturated acetyenic ketone is an important organic intermediate widely used in the synthesis of heterocyclic compounds, biomacromolecules, natural products, medicine, etc. Traditional synthetic methods of α, β unsaturated acetyenic ketone have certain shortcomings, such as harsh reaction condition, difficulty in obtaining substrates and low product yield. Carbonylative Sonogashira Coupling of iodo arene, a terminal acetylene compound and carbon monoxide is another way to synthesize α-β unsaturated acetyenic ketone. However, the existing Carbonylative Sonogashira Coupling reactions all use homogeneous palladium catalysts containing phosphine. The use of homogeneous palladium catalysts containing phosphine has the disadvantages of the toxicity of phosphine and difficulty in separation products from catalysts.
Researchers at the State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences (LICP), have developed a method for synthesizing α, β unsaturated acetyenic ketone compounds by carbonylation. They received a Chinese invention patent for the technique on July 4.
In this method, iodo arene, a terminal acetylene compound and carbon monoxide are used as reactants and activated carbon loaded palladium as a catalyst. The products are obtained through one to four hours’ reaction of reactants with the reaction temperature controlled between 80 and 140 ℃ and the pressure of the carbon monoxide between 0.5 and 3.0 MPa in the presence of a catalyst accelerator and a reaction solvent.
With the help of the method, the conversion rate can achieve 90%, with a selectivity of catalyst and products separation above 99% when the reaction is over. What's more, the catalyst can be reused and maintain its activity unchanged.
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