Table 1. Au(i)-catalyzed C–O bond formation with different NaO–R a .
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Entry | R–ONa | Solvent | Time (h) | Product | Yield b (%) |
1 | pCl-PhONa | CH3CN | 6 | >99 c | |
2 | HONa | MeOH | 8 | >99 | |
3 | MeONa | MeOH | 8 | >99 c | |
4 | EtONa | MeOH | 24 | >99 | |
5 | MeONa | EtOH | 24 | 86 (9) d | |
6 | EtONa | EtOH | 24 | 56 (78) e | |
7 | (2-Propoxide)Na f | 2-Propanol | 48 | 21 | |
8 | t-BuONa | tert-Butanol | 48 | 4 | |
9 | HONa | H2O | 24 | 34 (1af), 26 (1ag) | |
10 | MeONa | H2O | 24 | 52 (1af), 21 (1ag) |
aGeneral conditions: [2-(2-halophenyl)pyridine] = 20 mM, [alkoxide] = 40 mM, 0.5 mL solvent, 110 °C.
bCalculated with 1H-NMR spectroscopy using 1,3,5-trimethoxybenzene as the internal standard.
c Ref. 11.
dIn parentheses, the yield of the ethoxide insertion product.
eIn parentheses, the yield after 48 h.
fThe alkoxide was generated in situ adding 2 equivalents of sodium tert-butoxide as a base.