| 摘要 |
1,213,255. Acetylation. WACKER-CHEMIE G.m.b.H. 30 June, 1969 [28 June, 1968], No. 32923/69. Heading C2C. Compounds HCX 3 where X represents -CO-Y, -CN or one X is a hydrogen atom, and Y is OR, -N(R) 2 or R, and R is a branched or unbranched, saturated or unsaturated optionally substituted mono- or bivalent aliphatic or araliphatic radical (1-8C) or is anunsubstituted or substituted aryl radical are acetylated by reacting with ketene in the presence of an alkali metal salt of a carboxylic acid and/or a sulphonic acid at between -10‹ C. and 200‹ C. The preparation of triacetyl methane from acetylacetone, 3-acetoxy-crotonic acid ethyl ester and diacetyl acetic acid ethyl ester from acetoacetic acid ethyl ester, α- cyano-#-acetoxy-2-butenone acid methyl ester from cyanoacetic acid methyl ester, diacetylacetic acid allyl 2 - ethyl - hexyl and benzyl esters from the corresponding acetoacetic acid esters is described. The catalysts may be the salts of formic, acetic, chloracetic, propionic, butyric, isobutyric caprylic, capric, lauric, isotridecane and stearic acids or sulphoacetic, chlorosulphoacetic and sulphobenzoic acids and the process may be continuous or discontinuous in an inert solvent. |
