The organocatalyzed regioselective allylic trifluoromethylation of Morita-Baylis-Hillman adducts using Ruppert-Prakash reagent was achieved in high to excellent yields via a successive S(N)2'/S(N)2' mode for the first time. The reaction was extended to the asymmetric allylic trifluoromethylation by the use of a bis-cinchona alkaloid catalyst with high enantioselectivities up to 94% ee.

Two birds, one stone! The first kinetic resolution of allyl fluorides was achieved by the development of an organocatalyzed enantioselective allylic trifluoromethylation. Two kinds of chiral fluorinated compounds, which incorporate C*F and C*CF3 units, respectively, can thus be accessed by a single transformation.

Working together: The title reactions were achieved in high yields with high ee values (see scheme, (DHQD)2AQN=hydroquinidine(anthraquinone‐1,4‐diyl) diether). The cooperative catalysis of bis(cinchona alkaloid) and Lewis acid, particularly FeCl2, was effective for these transformations and gave the monofluoromethylation products with over 90 % ee and methylation products with up to 97 % ee.

Enantioselective trichloromethylation of Morita-Baylis-Hillman (MBH)-type allylic fluorides with chloroform (HCCl3 ) under organocatalysis was achieved with high to excellent enantioselectivities. Silicon-assisted CF bond activation by a Ruppert-Prakash reagent and direct activation of HCCl3 by a carbanion exchange process with trifluoromethyl (CF3 ) carbanion generated in situ from the Ruppert-Prakash reagent realized the direct asymmetric trichloromethylation at a stereogenic allylic positon, without any help from transition metal catalysis, and under very mild conditions. Pre-activation of HCCl3 was not required. This method was extended to the direct enantioselective introduction of other C-H compounds such as alkyne, arene, indene, and FBSM without any pre-activation under a metal-free system.

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