Patent GB-628397-A (GB)
Title: Improvements in or relating to beta-dithiocarbamyl carboxylic compounds and method of preparing same
Filed: 1946-09-04
Abstract: b -Dithiocarbamyl carboxylic acids and their polyvalent metal salts such as those of zinc, calcium, barium, lead, iron and cobalt, mixed polyvalent metal salts of such acids with other organic acids or mercaptans and complexes of the zinc salts with organic amines are accelerators and activators for the vulcanization of synthetic rubber and resins.  The free acids are modifiers for the polymerization of conjugated dienes such as butadiene-1,3.  The preparation of the compounds is described in Group IV (b).  Compounds instanced as accelerators are b -(diethyl-dithiocarbamyl)-propionic acid and the complex of cyclohexylamine with zinc b -dithiocarbamyl propionate.ALSO:b -Dithiocarbamyl carboxylic acid compounds are prepared by treating a b -lactone with a salt of a dithiocarbamic acid.  Polar solvents such as alcohol and water may be used, water being preferred.  Temperatures instanced range from - 20 DEG  to 200 DEG  C. the ranges 0 DEG  to 50 DEG  C. and with water 20 DEG  to 50 DEG  C. being preferred. The reactants are preferably used in equimolecular quantities. Salts of dithiocarbamic acids instanced are the alkali metal and ammonium salts of unsubstituted dithiocarbamic acid and dithiocarbamates prepared by treating an organic amine with carbon disulphide in alkaline solutions and which contain an organic radicle which may be either aliphatic, aromatic or alicyclic and is preferably composed of only carbon and hydrogen atoms attached to the nitrogen of the thiocarbamate structure.  Many compounds of the above classes of dithiocarbamates are listed, e.g. alkali metal and ammonium salts of dibutyl-, phenyl-, dibenzyl-, dicyclohexyl- and pentamethylene - dithiocarbamic acid.  b  - Propiolactone is the preferred lactone although many others are listed derived from saturated aliphatic b -hydroxy carboxylic acids which may contain cycloalkyl, aryl and aralkyl substituents and which may be further substituted with groups containing oxygen, nitrogen, sulphur or halogen.  Unsaturated b -lactones, and b -lactones of dicarboxylic acids and dilactones of dicarboxylic acids are also specified.  As examples of the above classes of b -lactones listed there may be mentioned b  - isovalerolactone, b  - cyclohexyl - b  - propiolactone, a -phenyl- and b -benzyl-b -propiolactone, a ,a  - dimethyl - b  - propiolactone - b -carboxylic acid, a  - hydroxy - b - phenyl - b -propiolactone and a -bromo-b -propiolactone-a -carboxylic acid.  In examples: b -propiolactone is added to an aqueous solution of ammonium dithiocarbamate to give (1) on acidification with hydrochloric acid b -dithiocarbamyl-propionic acid, and (2) on treatment with aqueous zinc chloride solution the zinc salt of b -dithiocarbamyl-propionic acid which forms a complex with cyclohexylamine and to (3) an aqueous solution of sodium diethyl dithiocarbamate to give on acidification with hydrochloric acid b  - (diethyl - dithiocarbamyl) - propionic acid.ALSO:b -dithiocarbamyl carboxylic acids and their polyvalent metal salts such as those of zinc, calcium, barium, lead, iron and cobalt, mixed polyvalent metal salts of such acids with other organic acids or mercaptons and complexes of the zinc salts with organic amines are accelerators and activators for the vulcanization of rubber.  For the preparation of the b -dithiocarbomyl compounds (see Group IV (b)).  Compounds instanced as accelerators are b -(diethyldithiocarbomyl)-propionic acid and the complex of cyclohexylamine with zinc b -dithiocarbomyl propionate.ALSO:b -Dithiocarbamyl-carboxylic acids and their alkali metal and ammonium salts (for preparation see Group IV) when combined with a fluent carrier are insecticides or fungicides.  Compounds instanced are ammonium and zinc b -dithiocarbamyl propionate and the complex of cyclohexylamine with zinc b -dithio-carbamyl propionate.