Table 1.

Reaction condition optimization for hydrofluorination of alkyne.^a

entry	HF complex (A-xHF)	T (°C)	solvent	yield (1a /2a /3a /4a)b
1	1 equiv KHSO4-13HF	rt	DCE	75% / 9% / 11% /5%
2	1 equiv K2SO4-14HF	rt	DCE	100% / 0 / 0 / 0
3	1 equiv Py-9HF	rt	DCE	100% / 0 / 0 / 0
4	1 equiv DMPU-12HF	rt	DCE	100% / 0 / 0 / 0
5	1 equiv KHSO4-13HF	rt	Toluene	79% / 8% / 8% / 5%
6	1 equiv KHSO4-13HF	rt	HFIP	29% /23% /20% /28%
7c	1 equiv K2SO4-14HF	rt	DCE	100% / 0 / 0 / 0
8d	1 equiv K2SO4-14HF	rt	DCE	100% / 0 / 0 / 0
9	1 equiv KHSO4-13HF	50	DCE	62% /13%/ 16% /9%
10	1 equiv DMPU-12HF + 1 equiv KHSO4-13HF	50	DCE	48% /27% /14% /11%
11e	2 equiv DMPU-12HF	50	DCE	100% / 0 / 0 / 0
12	2 equiv DMPU-12HF + 1 equiv KHSO4-13HF	50	Neat	6% / 65% /12% /16%
13	1 equiv DMPU-12HF + 0.5 equiv KHSO4-13HF	50	Neat	46% / 39% / 6% /9%
14	2 equiv DMPU-12HF + 0.5 equiv KHSO4-13HF	50	Neat	38 / 46% /6% /10%
15f	2 equiv DMPU-12HF + 1 equiv KHSO4-13HF	50	Neat	0 / 72% /12% /16%

^aReaction conditions: 1 (0.1 mmol), HF complex (1 equiv based on the complex A-xHF, equivalents of HF are x), solvent (0.1 mL), 1 hour.

^bNMR yields with benzotrifluoride as internal standard;

^c1 equiv TFA was added;

^d1 equiv TfOH was added;

^e1 equiv KHSO₄ was added;

^f3 h reaction time;