摘要 |
Process for the preparation of benzothiazolyl-2-sulphen-amides Akzo nv, Arnhem : The process for the preparation of benzothiazolyl-2-sulphenamides, by reacting a 2-mercaptobenzo-thiazole or dibenzothiazolyl 2,2'-disulphide with a primary or secondary aliphatic or cycloaliphatic amine in the presence of hydrogen peroxide as oxidizing agent in an aqueous medium is distinguished in that an aqueous hydrogen peroxide solution is metered at a temperature in the range from 30 to 70.degree.C into an aqueous suspension of the respective amine and the 2-mercaptobenzothiazole or dibenzothiazolyl 2,2'-disulphide in a ratio in the range between 1.0 and 1.5 mol of amine per mole of 2-mercapto-benzothiazole or per equivalent of dibenzothiazolyl 2,2'-disulphide, preferably in a quantity of below 1.35 mol per mole of 2-mercaptobenzothiazole or per equivalent of dibenzothiazolyl 2,2'-disulphide over a period of at least 60 minutes. The total quantity of water in the reaction mixture should not exceed 1500 g per mole of 2-mercaptobenzothiazole. An environmentally friendly and economic process is provided for the preparation of benzothiazolyl-2-sulphenamides in high yield and with high selectivity.
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