Chlorocarbonylsulfenyl chloride is the chemical compound with the formula . It is a colorless, distillable liquid that is related to phosgene. It features two reactive functional groups, an acyl chloride and a sulfenyl chloride. According to X-ray crystallography, the molecule is planar.
Preparation and reactions
Chlorocarbonylsulfenyl chloride is prepared by hydrolysis of trichloromethane sulfenyl chloride in sulfuric acid as solvent:
The compound, being bifunctional, has been used for the preparation of several heterocycles including oxathiazol-2-ones, oxathialones, and oxathiazoles.
Treatment with formamides gives dithiazolidinediones (also known as dithiasuccinoyl, or DTS).
Relevant to amino acid chemistry, ethylthionocarbamates react with chlorocarbonylsulfenyl chloride to give DTS derivatives:
Alcohols and amines react at the acyl chloride position to form alkoxycarbonylsulfenyl chlorides and carbamoylsulfenyl chlorides. Thiols selectively react at the sulfenyl chloride position to form S-alkylchlorocarbonyl disulfides:ROH + Cl–S–C(=O)–Cl → Cl–S–C(=O)–OR + HCl
RNH2 + Cl–S–C(=O)–Cl → Cl–S–C(=O)–NHR + HCl
RSH + Cl–S–C(=O)–Cl → RS–S–C(=O)–Cl + HClThese reagents are useful for the derivatization of biological thiols. Methoxycarbonylsulfenyl chloride, a related reagent derived from the above chemistry, is used in solid-phase peptide synthesis for selective disulfide bond formation via conversion of the acetamidomethyl (Acm) cysteine protecting group to thiol-labile S-alkylsulfenyl thiocarbonate (carbomethylsulfenyl, Scm) protecting group.
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