Patent GB-444262-A (GB)
Title: Improvements in the manufacture and production of condensation products containing sulphur
IPC: C07D209/86
Filed: 1934-09-24
Abstract: Thio ethers of N-vinyl pyrrole or of N-vinyl derivatives of compounds containing the pyrrole ring such as indole, carbazole, propylcarbazole, tetrahydrocarbazole, and naphthocarbazole are prepared by the interaction of hydrogen sulphide or of mercaptans, with the above N-vinyl compounds.  The latter are preferably prepared as described in Specification 438,281.  In the case of hydrogen sulphide the reaction is 2XN--CH = CH2+H2S --> XN.CH2.CH2.S--CH2.CH2.NX and in the case of mercaptans the reaction is y(XN--CH=CH2)+R(SH)y --> R.(XN.CH2.CH2--S)y, where R is an aliphatic, aliphatic-aromatic, aromatic, or heterocyclic radical, either unsubstituted, or substituted by halogen, nitro, alkoxy, or amino groups.  XN is the radical of pyrrole or a compound containing the pyrrole ring and y is one or a multiple of one.  Examples of mercaptans are methyl, ethyl, butyl, dodecyl, ethylene, and benzyl mercaptans, thiophenol, thiocresol, chlorthioxylene, thionaphthol, 1- or 2-mercaptoanthraquinone, thioresorcinol and mercaptobenzothiazole. The reaction may be carried out by direct addition of the reactants when both are liquids, or by leading in the hydrogen sulphide to either the vinyl compound itself if it is a liquid or to a solution of it in a suitable solvent such as ethanol, butanol, benzene, chlorbenzene, or toluene. Alternatively, the reaction may be carried out under pressure in an autoclave.  A small amount of a polymerization retarder such as an alkali, an alkali metal alcoholate, ammonia, or an organic base may be present.  Such substances also act as condensation catalysts.  The reaction is exothermic, and cooling measures are usually employed.  The yields are usually quantitative, and the products are purified by crystallization, distillation or precipitation.  They find application as dyestuff intermediates, as vulcanization accelerators, and for pharmaceutical purposes. In examples: (1) hydrogen sulphide is led into vinyl carbazole until no further absorption takes place, or alternatively the reaction may be conducted in an autoclave at 10--20 atmospheres to yield di-(carbazyl-N-ethyl)-sulphide; (2) hydrogen sulphide is led into a solution of vinyl indole in butanol to give di-(indole-N-ethyl)-sulphide; (3) a solution of vinyl carbazole and thiocresol in ethanol is heated to boiling for 12 hours to give carbazyl-N-ethyl-p-tolylsulphide.  In a similar manner vinyl carbazole and 1 : 4-dimethyl-2-chlor-5-mercaptobenzene yield the corresponding sulphide; (4) a solution of vinyl carbazole in toluene is added slowly to a solution of 2-mercaptoanthraquinone in toluene containing a little sodium ethylate to yield carbazyl - N - ethyl - 2 - mercaptoanthraquinone sulphide; (5) vinyl carbazole (2 mols.) is boiled in chlorbenzene solution with ethylene mercaptan (1 mol.) to give ethane-dithio-N-ethyl carbazole.ALSO:The vulcanization of rubber is accelerated by the addition to the mix of thio ethers of N-vinyl pyrrole or of N-vinyl derivatives of compounds containing the pyrrole ring such as indole, carbazole, propylcarbazole, tetrahydrocarbazole or napthocarbazole.  The compounds have either the general formula <FORM:0444262/V/1> or <FORM:0444262/V/2> , where R is an aliphatic, aliphatic-aromatic, aromatic, or heterocyclic radical either unsubstituted, or substituted by halogen, nitro, alkoxy, or amino groups.  XN is the radical of pyrrole or a compound containing the pyrrole ring, and y is one or a multiple of one.  The Specification contains numerous examples of compounds falling within the scope of the invention.