Table 2. Screening of the Ni-Catalyzed Carbonyl-Ene Reaction^a.

			yieldb (%)
entry	ligand	Ni source	20	21	combined	20:21
1	PPh3	Ni(cod)2	6	78	84	7:93
2	PPh3	1	7	81	88	8:92
3	PCy2Ph	Ni(cod)2	52	21	73	71:29
4	PCy2Ph	3	54	20	74	73:27
5	PCyPh2	2	17	56	73	23:77
6	PCy3	4	18	2	20	90:10

^aSee the Supporting Information for complete data for all complexes. Reactions were carried out on a 0.50 mmol scale with 20 mol % of catalyst and run for 48 h.

^bYields determined by gas chromatography calibrated against an internal standard of n-dodecane.