Table 2.

Scope of the Trifluoromethylation of Alkynyl- and Alkenyltrifluoroborates

Entry	Substrate	Method a	Product	Yield b
1	3a	A	5a	50% (−)
2	3b	A	5b	51% (45%)
3	4a	A	6a	54% (−)c
4	4b	A	6b	77% (77%)c
5	4c	A	6c	70% (59%)
6	4d	A	6d	12% (10%)
7	4e	A	-	-

^aConditions A: NaSO₂CF₃ (3.0 equiv), TBHP (5.0 equiv), CuCl (1.0 equiv), CH₂Cl₂/MeOH/H₂O, 1:1:0.8 ([3 or 4] = 0.1 M), open flask, rt, 12 h.

^bYields determined by ¹⁹F analysis; isolated yields are reported in brackets.

^cWith ~5% of the (Z) product.