Copper-Catalyzed Trifluoromethylthiolation Of Sodium Arylsulfinates

Compounds with trifluoromethylthio groups (-SCF3) and triflouromethyl groups (-CF3) are important products found in many agrochemical, pharmaceutical and veterinary drugs. In recent years, methods for introduction of CF3 into organic molecules have attracted much attention because of its strong electron-withdrawing effect and high lipophilicity. These properties are closely similar to trifluoromethylthio (-SCF3). Great advances in the study of trifluoromethylation have been achieved, whereas the trifluoromethylthiolations are less developed,we developed a new protocol of copper-catalyzed trifluoromethylthiolation of sodium arylsulfinates with TMSCF3. After screening the reaction parameters, we found the effective reaction conditions:0.1 equiv of CuSCN as catalyst,0.2 equiv of 8-aminoquinoline as the ligand,1.0 equiv of K3PO4 as base addictive, CH2C12 as solvent, and 5 equiv of TMSCF3 as the trifluoromethyl reagent, at 80℃ for 24 h under air. Twelve aryl triflouromethylthioethers and three vinyl triflouromethylthioethers were synthesized.we also developed a new protocol of TBAI-catalyzed desulfitative and denitrative trifluoromethylation. The effective reaction conditions for styryl sulfonyl hydrazides are presented as follows:0.1 equiv of TBAI as the catalyst,3 equiv of CF3SO2Na as the trifluoromethyl reagent,8 equiv of TBHP as oxidant, CH2C12/H2O as the solvent, at 70℃for 3 h under air. Five β-trifluoromethyl styrenes were synthesized. The effective reaction conditions for β-nitrostyrenes are presented as follows:0.2 equiv of TBAI as the catalyst,3 equiv of CF3SO2Na as the trifluoromethyl reagent,5 equiv of DTBP as oxidant,1.0 equiv of AgNO3 and TsOH as addictive, CH2C12/DMSO as the solvent, at 70℃for 24 h under air. Five β-trifluoromethyl styrenes were synthesized.In conclusion, we developed a new protocol of copper-catalyzed trifluoromethylthiolation and nonmetal-catalyzed triflouromethylation.