Table 1.
entry | solvent, temp | yieldb | entry | solvent, temp | yieldb |
---|---|---|---|---|---|
1 | toluene, 110 °C | 100% | 6 | t-amyl alcohol, 100 °C | 100% |
2 | acetone, 75 °C | 96% | 7 | MTBE, 80 °C | 100% |
3 | EtOAc, 100 °C | 100% | 8 | 2-Me-THF, 80 °C | 100% |
4 | i-PrOAc, 110 °C | 100% | 9 | DMSO, 110 °C | 0% |
5 | n-BuOH, 110 °C | 0% | 10 | acetonitrile, 100 °C | 99% |
Conditions: NiCl2(PCy3)2 complex (5 mol %), sulfamate substrate 1 (1.00 equiv), 2 (2.50 equiv), K3PO4 (4.50 equiv), hexamethylbenzene (0.10 equiv), 12 h.
Yield of 3 determined by 1H NMR analysis of crude reaction mixtures using hexamethylbenzene as an internal standard.