3,3-DiMethyl-1-[difluoro(phenylsulfonyl)Methyl]-1,2-benziodoxole

3,3-Dimethyl-1-[difluoro(phenylsul fonyl)methyl]-1,2-benziodoxole is a novel electrophilic difluoromethylation reagent prepared from TMSCF2SO2Ph, which can efficiently transfer the PhSO2CF2 moiety to nucleophiles such as thiols under mild reaction conditions. Copper(II)-catalyzed decarboxylative difluoro(phenylsulfonyl)methylation of α,β- or β,γ-unsaturated carboxylic acids with this reagent can afford vinylic and allylic difluoromethylation products.

(1) Difluoromethylation of thiols.

(2) Difluoromethylation of β,γ-unsaturated carboxylic acids.

(3) Difluoromethylation of α,β-unsaturated carboxylic acids.

[1] WEI ZHANG; Jinbo H; Jieming Zhu. Electrophilic (phenylsulfonyl)difluoromethylation of thiols with a hypervalent iodine(III)–CF2SO2Ph reagent[J]. Tetrahedron Letters, 2008. DOI:10.1016/j.tetlet.2008.06.064.
[2] ZHENGBIAO HE. Copper-Catalyzed Di- and Trifluoromethylation of α,β-Unsaturated Carboxylic Acids: A Protocol for Vinylic Fluoroalkylations?[J]. Angewandte Chemie International Edition, 2012, 51 16: 3944-3947. DOI:10.1002/anie.201200140.
[3] DR. ZHENGBIAO HE. Copper-Catalyzed Difluoromethylation of β,γ-Unsaturated Carboxylic Acids: An Efficient Allylic Difluoromethylation?[J]. Angewandte Chemie International Edition, 2012, 51 46: 11545-11547. DOI:10.1002/anie.201206556.