| 摘要 |
A method is provided for the preparation of a sucrose 6-ester by: (i) reacting sucrose with a trialkyl orthoester or with a ketene acetal in an inert organic solvent in the presence of an acid catalyst to provide a sucrose alkyl 4,6-orthoester, (ii) treating the sucrose alkyl 4,6-orthoester under mild aqueous acidic conditions to provide a mixture of sucrose 4- and 6-monoesters, (iii) treating the mixture of esters with a base to convert the sucrose 4-ester into sucrose 6-ester, and (iv) neutralising the solution and isolating the sucrose 6-ester, an acidic ion exchange resin being used to catalyse preparation of the sucrose alkyl 4,6-orthoester and to effect its hydrolysis. Sucralose is prepared by chlorinating the sucrose 6-esters prepared. |
