反应详情

A mixture of 12 from the monosilylation reaction was heated at 40° C. in anhydrous acetonitrile with K2CO3 (1.64 g, 11.8 mmol) and methyl iodide (4.2 g, 29.6 mmol) for 5 hours. The reaction mixture was worked up by addition of H2O and EtOAc. The organic layer was washed with H2O and the solvent was removed in vacuo. The residue was purified by column chromatography using a gradient of 10% EtOAc-Hex to elute the product 13 as a yellow solid (72% for two steps). 1H NMR (300 MHz, CDCl3) δ 1.13 (d, 18H, J=8 Hz), 1.53 (septet, 3H, J=7 Hz), 4.29 (s, 3H), 4.84 (s, 2H), 7.00 (t, 2H, J=8 Hz), 7.48 (dd, 2H, J=5, 8 Hz), 7.58 (dd, 1H, J=4, 8 Hz), 8.65 (dd, 1H, J=2, 8 Hz), 8.93 (dd, 1H, J=2, 4 Hz); EI MS (m/z) 509.7 [MH+], 531.4 [M+Na].

1. customfrom the monosilylation reaction
2. washThe organic layer was washed with H2O
3. customthe solvent was removed in vacuo
4. customThe residue was purified by column chromatography
5. washto elute the product 13 as a yellow solid (72% for two steps)