METHOD FOR SYNTHESIS ALKYL METHACRYLATES Russian patent published in 2011 - IPC C07C67/03 C07C69/54 

FIELD: chemistry.

SUBSTANCE: invention relates to synthesis of methacrylic esters - alkyl methacrylates. Alkyl methacrylates are obtained via reesterification of methyl methacrylate with fatty acids of general formula C_nH_2n+1OH, where n≥4, on a basic-type catalyst in the presence of a diethylhydroxylamine radical polymerisation inhibitor with distillation of the formed methanol in form of an azeotrope with methyl methacrylate. Before reesterification, the reaction mass which contains a fatty acid and methyl methacrylate in molar ratio 1:1.67-1.88 respectively, is dried in the presence of water-binding potassium or sodium carbonate, taken in amount of 0.056-0.07 wt % of the loaded methyl methacrylate. The reesterification process is carried out in the presence of diethylhydroxylamine in amount of 0.022-0.03 wt % of the total weight of loaded reagents, a sodium boron hydride catalyst in amount of 0.05-0.26 wt % or its alkyl ether in amount of 0.088-0.10 wt % of the fatty acid, or a mixture of sodium boron hydride in amount of 0.05-0.26 wt % and its alkyl ether in amount of 0.065-0.10 wt % of the fatty acid.

EFFECT: fewer number of steps and reduced amount of wastes, ensuring output of 97-99% of the loaded alcohols and high quality of the obtained product.

3 cl, 7 ex, 1 tbl