Preparation of carbamides useful as stabilisers

摘要

Prepn. of carbamides (I) carrying carbamyl gps., where R1 is H, alkyl, alkoxy, phenyl which can have substituents inert to amides and chlorosulphonyl isocyanates; R2 is H, mono- or di-substituted amine or alkoxy and R1 + R2 can form part of a heterocyclic nucleus, a is 0 to 5, b is 0 or 1 and a + b = 0 when R2 is H or heterocycle. The prepn. is achieved by reacting 1 mole of amide R1-NH-CO-(NH-CO)a (NH)b-R2 with 1 to 6 moles of chlorosulphonyl isocyanate in an inert solvent at -50 deg. to + 100 deg.C. and saponifying the N-sulphochlorides (II) formed, where X is H, -SO2Cl and at least one of X is -SO2Cl. (I) are used as additives in the textile industry and as stabilisers for plastics.