反应详情

Compound XIII is prepared by the following series of reactions: (1) ethyl m-toluate is brominated with N-bromosuccinimide in CCl4 to give ethyl 3-bromomethylbenzoate; (2) the bromo compound is treated with sodio bis-tert-butyl malonate and the product heated in toluene with a catalystic amount of a strong acid (preferably p-toluene-sulfonic acid) to effect elimination and decarboxylation and afford m-ethoxycarbonylhydrocinnamic acid; (3) the latter compound is made to react with thionyl chloride and the resulting acid chloride is reduced with potassium or sodium borohydride to yield ethyl 3-(3-hydroxypropyl)-benzoate; (4) the hydroxy ester is treated with phosphorus tribromide is ether to give reagent XIII.