Table 1.

Optimization of Reaction Conditions^a

Entry	Deviation from standard condition	Yield 12 (%)b	Yield 13 (%)c
1	None	66	28
2	1 equiv of cyclohexane	44	33
3	no photocatalyst	0	48
4	no ligand	3	27
5	no nickel	0	17
6	no light	0	34
7	26 °C	46	17
8	40 °C	55	32
9	no Na2WO4·2H2Od	39	19
10	no Na2WO4·2H2Od, 72 h	62	22
11	Na2SiO3·5H2O instead of Na2WO4·2H2O	57	25
12	no K3PO4d	58	35
13	no K3PO4, no Na2WO4·2H2O	17	11

^aK₃PO₄ (2 equiv); Na₂WO₄·2H₂O (1 equiv).

^bYields determined by ¹H NMR using 4-fluoroanisole as an external standard.

^cYield determined by GC analysis based on consumption of 2 equiv of chloroformate for production of 1 equiv of DPC.

^d3 equiv of base used.