申请人:Showa Denko K.K.
公开号:US04298530A1
公开(公告)日:1981-11-03
A process for producing 3-hydroxy-3-methylphthalide or its nuclearly substituted derivative of the following general formula ##STR1## wherein R represents a lower alkyl group, a lower alkoxy group, a lower alkoxycarbonyl group or a carboxyl group, and n is 0 or an integer of 1 to 3, which comprises reacting phthalic anhydride or its nuclearly substituted derivative of the following general formula ##STR2## wherein R and n are as defined, with malonic acid at an elevated temperature in at least one solvent selected from the group consisting of dialkylformamides, dialkylsulfoxides and aliphatic lower carboxylic acids in the presence of, as a catalyst, a salt of an inorganic or organic acid with a metal selected from the group consisting of metals of Groups IA, IIA, IIIB and VIII of the periodic table, manganese, copper and zinc.
生产3-羟基-3-甲基邻苯二酐或其核取代衍生物的方法,该方法包括在至少选择自二烷基甲酰胺、二烷基亚砜和脂肪族低碳酸中的一种溶剂中,在高温下,将邻苯二酐或其核取代衍生物与丙二酸反应,其中R代表低烷基基团、低烷氧基团、低烷氧羰基团或羧基,n为0或1至3的整数,所述反应在存在以下催化剂的条件下进行:选自周期表IA、IIA、IIIB和VIII族金属、锰、铜和锌的无机或有机酸盐。