Pptn. recovery of 2-amino-4,6-di:hydroxy:pyrimidine - by feeding aq. salt reaction prod. to vessel contg. strong and/or weak acid

摘要

Recovery of 2-amino-4,6-dihydroxypyrimidine (2-ADHP) from aq. solns. of its salts still contg. organic solvent and by-prods. from a 2-ADHP prodn. process is effected by feeding the soln. to a reactor vessel which already contains all or part of the necessary acid for 2-ADHP pptn.. USE/ADVANTAGE - The recovery process is claimed for aq.-alcohol solns. or alcohol dispersions of alkali 2-ADHP salts which have been obtd. by reaction of malonic esters with guanidine salts and alkali alcoholates, e.g. as per H. Rembold et al, Ber 96, p2796 (1963). Large-grained 2-ADHP (ave. grain size 10-80 microns) is obtd. which has good filterability and which can be washed with water instead of MeOH to give a quickly drying, non-clumping prod.