Amino-benzimidazole prodn. from ortho:phenylene di:amine - and cyanogen chloride in diluent useful as pharmaceutical and plant protective intermediate

摘要

Prodn. of 2-aminobenzimidazole (I) is carried out by reacting o-phenylenediamine (II) with CNCl in a suitable diluent (III) at -10 to 100 (+5 to 70) deg.C. Pref. (III) is water, a mixt. of water and an alkanol or a chlorohydrocarbon. (I) is an intermediate for pharmaceuticals and plant protectives. It is obtd. in a 1-stage reaction in a relatively short time, i.e. a few min, cf. the usual 5-6 hr. needed to achieve high yields if CNBr is used.