Table 1.

Catalytic Decarboxylative Trifluoromethylation Improved by DMEDA and an Activation Procedure^a

Entry	CuX (mol %)	DMEDA (mol %)	Activationb	% Yieldc (A : B)d
1e	I (100)	0	–	57 (2.6 : 1)
2	I (10)	0	–	65 (3.3 : 1)
3	I (10)	10	–	51 (3.6 : 1)
4	I (10)	10	√	75 (2.7 : 1)
5	TC (10)	10	√	52 (2.7 : 1)
6f,g	TC (5)	0	–	<5 (N.D.)
7f,h	TC (5)	0	–	0 (–)

^aReactions were performed with 1-Br (0.20 mmol), and KF (0.40 mmol) in DMF (0.20 mL).

^bActivation involved heating CuI, DMEDA, NaO₂CCF₂Br, and KF in DMF for 10 min prior to injection of 1-Br.

^cCombined yield of 2A and 2B as determined by ¹⁹F NMR analysis, using α,α,α-trifluorotoluene as an internal standard.

^dDetermined by ¹⁹F NMR spectroscopic analysis. ND = not determined.

^eDMF (0.60 mL).

^fKF (0.30 mmol), THF (1.2 mL), 20 h.

^gTMSCF₃ (0.30 mmol) was added to the reaction.

^h75% of 1-Br remained, as determined by ¹⁹F NMR spectroscopic analysis.