反应详情

A three-necked, 50-mL, round-bottomed flask was equipped with a magnetic stirrer, an ice bath, a standard condenser with a N2 inlet, and two glass stoppers. To a solution of 10% NaOH (8.94 g, 22.3 mmol) was added the amine (31, 1.14 g, 6.77 mmol) in CH2Cl2 (15 mL) in one portion. Dropwise addition of a solution of benzoyl chloride (1.05 g, 7.45 mmol) in CH2Cl2 (5 mL) to the mixture over 15 min under N2 was followed by stirring an additional 2.75 h at RT. After the addition of H2O (30 mL), the organic layer was separated. Additional extracts (CH2Cl2, 3×25 mL) were combined with the initial organic layer, dried (Na2SO4, 1 h), filtered, and concentrated (aspirator followed by vacuum pump, 1 h, RT/0.2 mm Hg) to give an orange oil. Chromatography of the oil was performed over neutral alumina (200 g, 2.1 cm×33 cm) with ethyl acetate as eluant. Fractions (Rf =0.70) were combined and concentrated (rotary evaporator then vacuum pump, overnight, RT/0.2 mm Hg) to yield 1.52 g (82.4%) of the amide (32) as an oil which was used without further purification. IR (film) cm-1 3085, 3065, 3035 (Ar C--H), 2970, 2925, 2865, 2805, 2780, 2750 (C--H), 1635 (C=O), 730, 710 (C--H out of plane, mono); 1H NMR (DCCl3) δ0.96 (d, 3 H, CH3, J=6.4 Hz), 1.07 (d, 3 H, CH3, J=6.6 Hz), 1.65-1.78, [m, 3 H, H(5) and H(9)], 1.97 [bs, 1 H, H(1)], 2.41 [d, 1 H, H(4)ax, J=10.3 Hz], 2.50 [d, 1 H, H(6)ax , J=11.0 Hz], 2.62 [m, 1 H, CH(CH3)2, J=6.5 Hz], 2.72 [d, 1 H, H(6)eq, J=10.6 Hz], 3.04-3.07 [m, 2 H, H(2)ax and H(4)eq ], 3.30 [d, 1 H, H(8)ax, J=13.2 Hz], 3.74 [d, 1 H, H(8)eq, J=12.8 Hz], 4.77 [d, 1 H, H(2)eq, J=13.9 Hz], 7.28-7.41 (m, 5 H, Ar--H); 13C NMR (DCCl3) ppm 16.30 (CH3), 19.33 (CH3), 29.06 [C(1)], 29.76 [C(5)], 32.29 [C(9)], 46.55 [C(2)], 52.19 [C(4)], 52.62 [C(8)], 54.34 [CH(CH3)2 ], 54.75 [C(6)], 126.75, 128.24, 128.67, 137.75 (Ar--C), 170.09 (C=O).

1. customA three-necked, 50-mL, round-bottomed flask was equipped with a magnetic stirrer, an ice bath, a standard condenser with a N2 inlet
2. customthe organic layer was separated
3. dry with materialdried (Na2SO4, 1 h)
4. filtrationfiltered
5. concentrationconcentrated (aspirator followed by vacuum pump, 1 h, RT/0.2 mm Hg)
6. customto give an orange oil
7. concentrationconcentrated (
8. customrotary evaporator