Isopropylsulfonyl chloride

Chemical Properties

Clear pale yellow-greenish liquid

Uses

2-Propanesulfonyl chloride is used as a pharmaceutical intermediate. Reductive cleavage of a secondary alcohol to methylene has been achieved by reduction of the 2-propanesulfonyl ester with lithium triethylborohydride.

Uses

2-Propanesulfonyl chloride (isopropylsulfonyl chloride) can be used as a reactant to prepare:

• 1-Isopropylsulfonyl-2-amine benzimidazole by reacting with 2-aminobenzimidazole via N-sulfonylation reaction in the presence of a base.
• Bis(isopropylsulfonyl)disulfide, a sulfurizing agent, used to synthesize phosphorothioate oligonucleotide analogs.

General Description

The solvolysis of 2-propanesulfonyl chloride by an addition-elimination (association-dissociation) pathway was studied.

Synthesis

75-33-2

10147-37-2

The general procedure for the synthesis of isopropylsulfonyl chloride from isopropyl mercaptan is as follows: a solution of isopropyl mercaptan (1 eq.) and isopropanol (2 eq.) was stirred in dichloromethane (0.15 M). Subsequently, N-bromosuccinimide (4 eq.) or N-chlorosuccinimide (3.5 eq.) was added in batches at room temperature (when N-bromosuccinimide was used) or at 0 °C (when N-chlorosuccinimide was used). The reaction mixture was stirred at room temperature until the starting material was undetectable by thin layer chromatography (TLC) (about 1 hour). After completion of the reaction, the reaction mixture was diluted with cold saturated sodium bicarbonate solution and extracted with ethyl acetate (four times). The organic extracts were combined, dried with sodium sulfate and subsequently concentrated under vacuum to give the crude product. Finally, pure isopropylsulfonyl chloride was purified by silica gel column chromatography or radial chromatography using a hexane/ethyl acetate/acetone solvent mixture as eluent to give pure isopropylsulfonyl chloride.

References

[1] Chemistry Letters, 1992, # 8, p. 1483 - 1486
[2] Tetrahedron Letters, 2017, vol. 58, # 23, p. 2244 - 2247
[3] Journal fuer Praktische Chemie (Leipzig), 1979, vol. 321, p. 279 - 292
[4] Journal fuer Praktische Chemie (Leipzig), 1969, vol. 311, p. 596 - 603
[5] Journal fuer Praktische Chemie/Chemiker-Zeitung, 1992, vol. 334, # 3, p. 251 - 256