| 摘要 |
1,177,591. Acetoacetic acid esters. WACKERCHEMIE G.m.b.H. 5 Jan., 1968 [10 Jan., 1967], No. 848/68. Heading C2C. Acetoacetic acid-esters are prepared by reacting diketene with a saturated aliphatic alcohol, e.g. having 1-8 carbon atoms at a reaction temperature between the boiling point of the alcohol used and the boiling point of the ester formed, in the presence of, as catalyst, at least one alkali metal salt of at least one acid having a pH value below 3À0. Examples of the catalyst include alkali metal halides and sulphates and alkali metal salts of an α-chlorocarboxylic acid, e.g. α-chloroacetates. |
