Method for preparing bis(organotin mercaptoalkanol ester) sulfides

Claim 1

A method for preparing an organotin compound of the general formula ##STR3## wherein R and R' are individually selected from the group consisting of alkyl containing from 1 to 20 carbon atoms, cycloalkyl, aralkyl, aryl and alkaryl, m is 2 or 3 and p is 1 or 2, said method consisting essentially of the following sequence of steps: (1) reacting a monoorganotin trihalide of the formula RSnX 3 , a diorganotin dihalide of the formula R 2 SnX 2 or an equimolar mixture of RSnX 3 and R 2 SnX 2 wherein X is a halogen selected from the group consisting of chlorine, bromine and iodine, with an aqueous solution containing a base selected from the group consisting of ammonium hydroxide, alkali metal hydroxides and alkali metal alkoxides, wherein the ratio of the number of equivalent weights of base to the number of moles of halogen initially present on the organotin halide is n-2:n, respectively, and the rate at which the reagents are combined is adjusted to avoid excessive overheating of the reaction mixture; (2) adding n-2 moles of 2-mercaptoethanol or 3-mercaptopropanol to the resultant mixture; (3) gradually adding to the reaction product of step 2 an alkali metal sulfide when p is 1 or an alkali metal disulfide when p is 2, the number of moles of sulfide or disulfide being equal to 0.5 times the number of moles of tin present in said reaction product; (4) reacting the product obtained thereby with n-2 moles of a carboxylic acid, R'COOH, or an ester R'COOR" wherein R" is alkyl and contains from 1 to 20 carbon atoms; (5) removing any by-product water from the resultant mixture to isolate said organotin compound.

Claim 2

A method for preparing an organotin compound of the general formula ##STR3## wherein R and R' are individually selected from the group consisting of alkyl containing from 1 to 20 carbon atoms, cycloalkyl, aralkyl, aryl and alkaryl, m is 2 or 3 and p is 1 or 2, said method consisting essentially of the following sequence of steps: (1) reacting a monoorganotin trihalide of the formula RSnX 3 , a diorganotin dihalide of the formula R 2 SnX 2 or an equimolar mixture of RSnX 3 and R 2 SnX 2 wherein X is a halogen selected from the group consisting of chlorine, bromine and iodine, with an aqueous solution containing a base selected from the group consisting of ammonium hydroxide, alkali metal hydroxides and alkali metal alkoxides, wherein the ratio of the number of equivalent weights of base to the number of moles of halogen initially present on the organotin halide is n-2:n, respectively, and the rate at which the reagents are combined is adjusted to avoid excessive overheating of the reaction mixture; (2) adding n-2 moles of 2-mercaptoethanol or 3-mercaptopropanol to the resultant mixture; (3) gradually adding to the reaction product of step 2 an alkali metal sulfide when p is 1 or an alkali metal disulfide when p is 2, the number of moles of sulfide or disulfide being equal to 0.5 times the number of moles of tin present in said reaction product; (4) reacting the product obtained thereby with n-2 moles of a carboxylic acid, R'COOH, or an ester R'COOR" wherein R" is alkyl and contains from 1 to 20 carbon atoms; (5) removing any by-product water from the resultant mixture to isolate said organotin compound.