In
organosulfur chemistry, a sulfenyl chloride is a
functional group with the connectivity R−S−Cl, where R is
alkyl[1] or
aryl. Sulfenyl chlorides are reactive compounds that behave as sources of RS+. They are used in the formation of RS−N and RS−O bonds. According to
IUPAC nomenclature they are named as alkyl thiohypochlorites, i.e.
esters of thiohypochlorous acid.
Typically, sulfenyl halides are stabilized by
electronegative substituents. This trend is illustrated by the stability of CCl3SCl obtained by chlorination of
carbon disulfide.
Sulfenyl chlorides can be converted to
sulfinyl chlorides (RS(O)Cl). In one approach, the sulfinyl chloride is generated in two steps starting with reaction of a
thiol (−SH) with
sulfuryl chloride (SO2Cl2). In some cases the sulfenyl chloride results instead, as happens with 2,2,2-trifluoro-1,1-diphenyl
ethanethiol. A
trifluoroperacetic acid oxidation then provides a general approach to formation of sulfinyl chlorides from sulfenyl chlorides:[11]
Sulfenyl iodides can be isolated as stable compounds if they bear alkyl steric protecting groups as part of a cavity-shaped framework, illustrating the technique of kinetic stabilization of a reactive functionality, as in the case of
sulfenic acids.[13]
A related class of compounds are the alkylsulfur trichlorides, as exemplified by methylsulfur trichloride, CH3SCl3.[14]
The corresponding selenenyl halides, R−SeCl, are more commonly encountered in the laboratory. Sulfenyl chlorides are used in the production of agents used in the
vulcanization of rubber.
References
^Drabowicz, J.; Kiełbasiński, P.; Łyżwa, P.; Zając, A.; Mikołajczyk, M. (2008). Kambe, N. (ed.). Alkanesulfenyl Halides. Science of Synthesis. Vol. 39. pp. 544–550.
ISBN9781588905307.