[31206-25-4] · C6H3ClN2O6S · 3,5-Dinitrobenzenesulfonyl Chloride · (MW 266.63)
Physical Data: mp 98.5 °C.
Solubility: sol AcOH, pyridine; insol diethyl ether.
Form Supplied in: not commercially available; easily prepared.
Preparative Method: by a modified Sandmeyer reaction.3,4 Diazotization of 3,5-dinitroaniline (0.25 mol) at -15 °C in aqueous acetic acid/conc HCl followed by addition to a saturated solution of SO2 in acetic acid gives the product, which is precipitated by the addition of water, washed with water then diethyl ether, and dried under vacuum (81% yield).
Handling, Storage, and Precautions: reactive sulfonylating agent: avoid contact with skin and mucous membranes. Can be stored at rt for prolonged periods when dried and kept free of moisture.
Arenesulfonyl chlorides are vital precursors for the preparation of a wide variety of functional groups including sulfonate esters, sulfonamides, and sulfones. A variety of substituted arenesulfonyl chlorides can be used to derivatize alcohols and primary and secondary amines forming sulfonate esters and sulfonamides, respectively. Substituted arenesulfonate esters exhibit varying rates of SN1 and SN2 reactions which are dependent on the aryl substituents.2
Solvolysis of the crystalline 3,5-dinitrobenzenesulfonate of 3-pentyn-1-ol in CF3CO2H-CF3CO2Na gives 2-methylcyclobutanone1 in 73% yield (eq 1). The yield of 2-methylcyclobutanone was reduced when the p-toluene- and m-nitrobenzenesulfonates were used. Cyclobutanone5 and other alkyl-substituted cyclobutanones6 have also been prepared via this participation of an alkynic bond during solvolysis of homopropargylic sulfonate esters, but the former requires the use of the more reactive trifluoromethanesulfonate.
John L. Esker & Carl R. Johnson
Wayne State University, Detroit, MI, USA