Table 4.
| ||||||
---|---|---|---|---|---|---|
entry | conditionsb | Yield P (%) |
Yield B (%) |
Yield E (%) |
||
PhI | Mn0 | Et3SiCl | ||||
1 | 0 | 0 | 0 | 0 | 0 | 0 |
2 | 100 | 0 | 0 | 12 | 0 | 0 |
3 | 100 | 0 | 110 | 7 | 0 | 0 |
4 | 100 | 110 | 200 | 71 | 0 | 0 |
5 | 1.0 | 110 | 200 | 28 | 0 | 0 |
6 | 100 | 0d | 0 | 26 | 0 | 0 |
7 | catalytic reaction with Ni(acac)2 and L10 | 99e | 0 | 13e | ||
8 | Catalytic reaction with Ni(acac)2, L10, and pyr | 69e | 0 | 14e |
Nickel complexes were generated in situ at a concentration of 2.5 mM in DMA and reacted with the noted reagents. Analysis at 5 minutes (GC, corrected) provided the stated yields. For stoichiometric reactions (1–6), the yield is calculated from starting nickel complex IIA.
Equivalents with respect to [Ni].
Mn0 powder was pre-stirred with Et3SiCl.
TDAE = tetrakis(dimethylamino)ethylene.
Yield calculated from the amount of enone added to catalytic reactions (0.5 mmol).