Sulfoxide, methyl 2-chlorophenyl

Oae and Khim measured the rates of hydrolysis of chlorophenyl phenyl sulfoxides and sulfones with hydroxide ion in aqueous DMSO at 158 °C. Both SOPh and S02Ph were found to activate the nucleophilic substitution from ortho- and para-positions, but the effect of SOjPh was considerably larger than that of SOPh. The results were interpreted in terms of 7t(pd) conjugation in the intermediate complexes. In a later paper it was shown that the introduction of a methyl group ortho to SOPh or S02Ph slightly retards the above and related reactions but this was attributed to the inductive effect of Me rather than steric inhibition of 7t(pd) conjugation (Section III.A.l). 

It was reported earher that the oxidation of a sulfoxide to a sulfone involves either an initial nucleophihc attack of the nucleophilic oxidant or an electrophihc attack by an electrophilic oxidant. It is noteworthy that the oxidation of p-tolyl methyl, phenyl methyl and p-chlorophenyl methyl sulfoxides to the sulfones using the sulfonylperoxy intermediate 51 appears to be electrophihc, namely the relative reactivity order was p-tolyl methyl > phenyl methyl > p-chlorophenyl methyl sulfoxide based on competitive oxidations. 

Figure 12 Inclusion compound of (f )-2-chlorophenyl methyl sulfoxide by 1. (a) Layer structure, (b) Packing (CPK model) of the inclusion compound. For clarity, phenyl groups of 1 and guest are unshaded and gray, respectively.

Cis- and frans-3-f-butyl (or 3-p-chlorophenyl) thietane 1-oxides are isomerized on treatment with hydrogen chloride in dioxane. Mixtures of varying isomer composition yield equilibrium mixtures consisting of 85-100% of the cis isomer. A similar result is obtained by heating the sulfoxides at 170-175° in decalin. Likewise, 3-methyl-3-phenylthietane 1-oxide may be isomerized to an equilibrium mixture consisting mainly (74%) of the equatorial, c/s-3-phenyl isomer. ... 

Thake DC, Mays DC, Leber AP, Dacre JC (1993) p-Chlorophenyl methyl sulfide, p-chlorophenyl methyl sulfoxide and p-chlorophenyl methyl sulfone. II. Subchronic effects in rodents and rhesus monkeys. J Americ College Toxicol 12, 377-395. 

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