| 摘要 |
1510741 Di(acyloxy)alkenes IMPERIAL CHEMICAL INDUSTRIES Ltd 21 Jan 1977 [19 Feb 1976] 06610/76 Heading C2C Diacyloxyalkenes are prepared by contacting a conjugated diene, a carboxylic acid and anhydride and oxygen in the vapour phase with a solid catalyst comprising palladium and at least one promoting element of Periodic Groups V and VI selected from P, As, Sb, Bi, Se and Te. The anhydride is preferably in a proportion of at least 1 mole per cent of the acid and may be from 5 to 25 mole per cent of the acid. A catalyst support such as silica, alumina, magnesia, kieselguhr, pumice and carbon may be used. Antimony is the preferred promoting element and alkali or alkaline earth metal carboxylates may also be included. Examples describe the preparation of diacetoxybutenes using antimony as the promoter and including caesium acetate and tetramethylammonium acetate. |
