反应详情

A stirred solution of 2d (1.04 g, 1.8 mmol) in dry THF (35 mL) at -78° C. was treated dropwise with a THF solution of BH3 ·SMe2 (2M, 1.8 mL) while maintained under a blanket of argon. The reaction mixture was allowed to reach room temperature during the course of 3 h and was stirred further for 12 h. Evaporation of the solvent under reduced pressure gave a residue that was dissolved in dry CH2Cl2 (100 mL) and treated with pyridinium chlorochromate (PCC, 15 g, 69.5 mmol). The dark reaction mixture was stirred at room temperature for 3 days and was diluted with dry ether (500 mL) before being filtered through a short silica gel column. The solution obtained was dried (Na2SO4) and reduced to dryness. The residue was purified by flash column chromatography over silica gel using 10% EtOAc in hexane as eluant to give 3d (0.758 g, 71%) as a pale yellow oil; IR (neat) 1785.6, 1743.5 cm-1 ; 1H NMR (CDCl3) δ 0.87 (distorted t, 3 H, CH3), 1.05 (s, 9 H, C(CH3)3), 1.25 (m, 20 H, CH3 (CH2)10CH2CH2CO); 1.55 (m, 2 H, CH3 (CH2)10CH2CH2CO), 2.00-2.40 (m, 4 H, H-4, CH3 (CH2)10CH2CH2CO), 2.60 (m, 2 H, H-3), 3.70 (AB q, J=10.8 Hz, 2 H, CH2OSi), 4.20 (AB q, J=12.0 Hz, 2 H, CH2OCO), 7.30-7.70 (m, 10 H, Ph); 13C NMR δ 14.10, 19.17, 22.67, 24.78. 25.91, 26.72, 28.87, 29.08, 29.20, 29.33, 29.41, 29.57, 29.62, 31.90, 34.03, 65.64, 66.15, 85.77, 127.88, 130.01, 132.25, 132.50, 135.52, 135.59, 173.15, 176.28. Anal. Calcd for C36H54O5Si: C,72.68; H, 9.16. Found: C,72.76; H, 9.22.

1. temperaturewhile maintained under a blanket of argon
2. customto reach room temperature during the course of 3 h
3. customEvaporation of the solvent under reduced pressure
4. customgave a residue that
5. customThe dark reaction mixture
6. stirringwas stirred at room temperature for 3 days
7. filtrationbefore being filtered through a short silica gel column
8. customThe solution obtained
9. dry with materialwas dried (Na2SO4)
10. customThe residue was purified by flash column chromatography over silica gel using 10% EtOAc in hexane as eluant