申请人:Hoechst AG
公开号:US05539114A1
公开(公告)日:1996-07-23
A process for the preparation of quinazoline-2,4-diones of the formula (I) ##STR1## in which R.sup.1 is aryl and R.sub.2, R.sup.3, R.sup.4, and R.sup.5 independently of one another are halogen, alkyl, alkoxy or hydrogen, by reacting anthranilic acid esters of the formula (II) ##STR2## in an aprotic reaction medium with aryl isocyanates R.sup.1 --N.dbd.C.dbd.O to give N-arylcarbamoyl-anthranilic acid esters of the formula (III) ##STR3## and cyclizing these in the presence of a base selected from the group of alkali metal or alkaline earth metal alkoxides, amides, hydrides or tetraalkylammonium hydroxides.
一种制备式(I)的喹唑啉-2,4-二酮的方法,其中R.sup.1为芳基,R.sub.2,R.sup.3,R.sup.4和R.sup.5彼此独立地为卤素,烷基,烷氧基或氢,通过将式(II)的蒽酰氨酸酯与芳基异氰酸酯R.sup.1-N.dbd.C.dbd.O在无极溶剂反应介质中反应,以给出式(III)的N-芳基氨甲酰蒽酰氨酸酯,并在碱金属或碱土金属醇,酰胺,氢化物或四烷基铵氢氧化物组成的基组中环化。