Chlorocarbonylsulphenyl chloride

Benzothiazolones are useful intermediates in the synthesis of plant growth regulators, and may be synthesized from substituted anilines by first converting the latter (with formaldehyde) into l,3,5-(triaminoaryl)-l,3,5-triazines which then break down on stirring successively with chlorocarbonylsulphenyl chloride and aluminium chloride. 

A convenient synthesis of sulphenyl chlorides has been developed in which a thiol is reacted with chlorocarbonylsulphenyl chloride and the resulting adduct desulphurized by triphenylphosphine. Further examples - have been enumerated in which olefins are stereospecifically synthesized by a two-fold extrusion process, one of which is the removal of sulphur by a phosphine, e.g. in the synthesis of bicyclobutylidene (25). 

Tanabe et al. have described a regioselective [2 -t- 3] cyclocondensation between chlorocarbonylsulphenyl chloride (ClCOSCl) and 2-aminobenzothiazoles which produced 3H-l,2,4-thiadiazolo[3,4-b]benzothiazol-3-ones (90) <97H1579>. 

Thiazolo-[2,3-c]- and -[3,2-6]-[l,2,4]thiadiazoles [CaNgS-CaNS].—Condensations of a-amino-N-heterocycles with chlorocarbonylsulphenyl chloride in the presence of an organic tertiary base can give rise either to a 2,3- or to a 3,4-fused [1,2,4]-thiadiazolone. Thus, 2-aminothiazole yields 2JT-thiazolo[3,2-b][l,2,4]thiadiazol-2-one in THF (see Vol. 3, p. 684). The isomeric 2,3-fused system is formed in ethanol-free chloroform. 2-Amino-A -thiazoline similarly yields 5,6-dihydro-thiazolo[2,3-c][l,2,4]thiadiazol-3-one, the structure of which has been confirmed by X-TQ.y analysis. ... 

Chlorocarbonylsulphenyl chloride ClCOSCl and related compounds have uses in synthesis, of thiazol-2-ones, and of alkyl chlorides from the corresponding thiols. The latter procedure involves a disulphide RSSCOCl, treatment with PhB giving the alkyl chloride, though some elimination accompanies the substitution reaction, and is the major reaction for cyclohexanethiol. Whereas aminolysis of ClCOSCl occurs at carbonyl carbon, that of FCOSCl involves displacement of Cl from S. ... 

Diethylaminopropyne and chlorocarbonylsulphenyl chloride react addi-tively to form the intermediate adduct (173) as a cis-trans mixture. On distillation this loses chloroethane, giving 4-chloro-3-ethyl-4-methyl-A -thia-zolin-2-one (174) since only the frans-isomer is cyclizable, the yields are moderate. ... 

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