Synthesis of (1,213C)-2-chloroethyl phenyl sulfide

Incorporation of a double 13C label into the mustard 2-chloroethyl phenyl sulfide is straightforward, but analysis is complicated by 13C-13C coupling. An alternative is reported, in which the ease of scrambling of sulfur mustards is used to advantage to prepare precisely 50% (1, 2-13C) enriched with each carbon of the ethyl chain labelled to provide optimal signal to noise in the 13C spectrum. (author)