| 摘要 |
1,232,668. Production ofα,#-unsaturated compounds. EASTMAN KODAK CO. 18 Oct., 1968 [23 Oct., 1967], No. 49515/68. Heading C2C.α,#-Unsaturated aldehydes, ketones, nitriles or carboxylic esters in which there is a CH 2 = group at the #-position are obtained by reacting formaldehyde with a saturated aliphatic aldehyde, aliphatic ketone, aliphatic nitrile or alkyl ester of a saturated aliphatic carboxylic acid, respectively, said aldehyde, ketone, nitrile or ester possessing at least two hydrogen atoms bonded to theα-carbon atom and having one less carbon atom than the unsaturated compound obtained as product, in the presence of a catalyst comprising a silica gel which has a pore volume greater than 0.30 c.c. per gram and a surface area less than 600 square metres per gram and which is free from basic metal compounds. The reaction is suitably effected in the gaseous or vapour state at a temperature of 350-525‹ C. employing a molar ratio of ester, aldehyde, ketone or nitrile to formaldehyde in the range of 1 : 1 to 25 : 1. Specific examples describe the production of methyl methacrylate, methyl acrylate, acrolein, methacrolein, 1- ethyl acrolein, methyl vinyl ketone, methyl isopropenyl ketone, acrylonitrile, methacrylonitrile and 1-ethyl acrylonitrile. |
