Herein, we describe the first asymmetric 3-CR between 2,2,2trifluorodiazoethane (1), EBX derivatives and nucleophiles for the synthesis of trifluoromethylated propargylic ethers and anilines. The reaction proceeds with high enantioselectivity for non-chiral alcohols and anilines and high diastereoselectivity under catalyst control for chiral alcohols. In the case of alcohol nucleophiles, primary, secondary and tertiary alcohols could all be used, the latest being challenging targets for traditional etherification reactions. As a model system, we chose the 3-CR of 2,2,2-trifluorodiazoethane (1), EthynylBenziodoxole (EBx) 2a and cyclohexanol (3a) (Table ). After optimization, the enantioselective 3-CR could be performed using commercially available Cu(MeCN)4BF4 and BOX ligand L1 at room temperature using DCE as solvent to give product 4aa in 85% yield and 96:4 er after 1 h of reaction (Table ). On 0.20 mmol scale, 4aa could be isolated in 83% yield. With indaBOX ligand L2, a quantitative yield, but lower selectivity was obtained (Table , entry 2). Using similar conditions than in our previous enantioselective oxyalkynylation work 20b -generation of a cationic complex in situ from CuCl/AgNTf2 in presence of L1 or L2-led to similar results (Table and). Other counterions, such as SbF6 -, PF6 -or OTf -gave 4aa in similar or lower yields and er (Table ). Different Cu(I) catalysts, such as Cu(OTf)•PhMe, CuI or CuTc, (Table , entry 8 and Supporting Information) were also tested, but no improvement was observed. Using Cu(II) salts, such as Cu(OAc)2 or Cu(OTf)2 was also less efficient (Table , entries 9-10). A larger excess of 3a did not lead to a significant improvement (Table , entry 11). Using only 1.5 equiv of 3a afforded compound 4aa in lower yield, but similar selectivity (Table , entry 12). Non-chlorinated solvents were also tested. No reaction was observed with MeCN and a lower yield and similar selectivity than with DCE when using PhMe. (Table , entries 13-14). Further solvents and conditions were also tested but did not lead to any improvements (see Supporting Information).