Solvent-controlled nucleophilic trifluoromethylthiolation of Morita–Baylis–Hillman carbonates: dual roles of DABCO in activating the Zard's trifluoromethylthiolation reagent and the MBH carbonates†
Abstract
A novel amine-catalyzed nucleophilic trifluoromethylthiolation between Morita–Baylis–Hillman carbonates and O-octadecyl-S-trifluorothiolcarbonate has been developed. The regioselectivity of this reaction can be controlled by choosing different solvents, affording primary allylic SCF3 products in THF and secondary allylic SCF3 products in CHCl3 as major products. The mechanistic investigation indicated that DABCO plays a dual role in activating the Zard's trifluoromethylthiolation reagent and the MBH carbonates.