Table 1.

Reaction Development and Control Experiments^a

entry	deviation from conditions above	yieldb (%)
1	no light (rt or 80 °C)	0
2	13 W 405 nm LED	93
3	no nickel salt	0
4	5 mol% NiBr2·glyme	95
5	5 mol% NiCl2·6H2O	95
6	no quinuclidine base	55
7	no quinuclidine, 3.5 equiv morpholine	94 (87)c
8	1.5 equiv DBU base	2
9	same as entry 7, presence of oxygend	91
10	1 h	72

^a0.4 mmol scale. Abbreviations: DMAc, N,N-dimethylacetamide; rt, room temperature; LED, light-emitting diode; DBU, 1,8-diazabicyclo-[5.4.0]undec-7-ene.

^bYield determined by ¹⁹F NMR.

^cIsolated yield.

^dDeoxygenated reaction mixture sparged with air for 2 min prior to light irradiation.