| 摘要 |
PCT No. PCT/EP92/02917 Sec. 371 Date Jun. 21, 1994 Sec. 102(e) Date Jun. 21, 1994 PCT Filed Dec. 16, 1992 PCT Pub. No. WO93/13084 PCT Pub. Date Jul. 8, 1993.The process for the preparation of benzothiazolyl-2-sulphenamides, by reacting a 2-mercaptobenzothiazole 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 DEG to 70 DEG 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-mercaptobenzothiazole 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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