申请人:Ciba-Geigy Corporation
公开号:US04020098A1
公开(公告)日:1977-04-26
According to the present invention, 5-substituted resorcinols of the formula I ##STR1## wherein R.sub.1 represents a hydrocarbon radical, optionally unsubstituted or substituted by inert substituents, are prepared by reacting a carboxylic acid ester of the formula II r.sub.1 -- c .tbd. c -- co -- o -- r.sub.2 (ii) wherein R.sub.2 represents a non-aromatically bound lower hydrocarbon radical, in the presence of an alkaline condensation agent, with a diester of 3-oxoglutaric acid of the formula III r.sub.3 --o--co--ch.sub.2 --co--ch.sub.2 --co--o--r.sub.4 (iii) wherein R.sub.3 and R.sub.4 represent non-aromatically bound lower hydrocarbon radicals; hydrolyzing the resulting dihydroxyisophthalic acid acid ester of the formula IV ##STR2## and decarboxylating the hydrolyzed product, a specific embodiment is the preparation of 5-pentylresorcinol.
根据本发明,通过在碱性缩聚剂存在下,将式I的5-取代间苯二酚与式II的羧酸酯进行反应制备,其中R₁代表一个烃基,可以是未取代或被惰性取代基取代;反应的羧酸酯为式II:r₁--c.tbd.c--co--o--r₂ (ii),其中R₂代表非芳香键合的较低碳氢基;与式III的3-氧代戊二酸二酯进行反应,制备5-戊基间苯二酚。其中,式III为:r₃--o--co--ch₂--co--ch₂--co--o--r₄ (iii),其中R₃和R₄代表非芳香键合的较低碳氢基;水解生成的二羟基异苯二甲酸酯为式IV:并脱羧水解产物,特定实施例为制备5-戊基间苯二酚。