反应详情

To a stirred solution of N-(tert-butoxycarbonyl)-D-phenylalanine (11.0 g, 41.5 mmol) in chloroform (125 mL) was added 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride (7.95 g, 41.5 mmol) and 1-hydroxybenzotriazole (5.60 g, 41.4 mmol). After 5 minutes, 2,2-diphenylethylamine (7.44 g, 37.7 mmol) was added. The reaction was stirred for 2 hours, diluted with chloroform (100 mL) and washed with aqueous sodium bicarbonate solution. The organic layer was dried (sodium sulfate) and concentrated to afford an off-white solid. Trituration with ether afforded the crude amide. This material was taken up in methylene chloride (100 mL) and treated with trifluoroacetic acid (45 mL, 580 mmol). After stirring for 15 minutes, the reaction was concentrated and the residue was partitioned between ethyl acetate and aqueous sodium bicarbonate. The organic layer was dried (sodium sulfate) and concentrated to afford 12.4 g (111% yield inflated by entrained residual solvent) of product as a colorless gum: 1H NMR (CDCl3) δ 7.34–6.95 (m, 15H), 4.10 (t, J=8.2, 1H), 3.88–3.79 (m, 2H), 3.68–3.61 (m, 1H), 3.49 (br s, 2H), 3.13–3.03 (m, 1H), 2.70–2.59 (m, 1H) ppm.

1. washwashed with aqueous sodium bicarbonate solution
2. dry with materialThe organic layer was dried (sodium sulfate)
3. concentrationconcentrated
4. customto afford an off-white solid
5. stirringAfter stirring for 15 minutes
6. concentrationthe reaction was concentrated
7. customthe residue was partitioned between ethyl acetate and aqueous sodium bicarbonate
8. dry with materialThe organic layer was dried (sodium sulfate)
9. concentrationconcentrated
10. customto afford 12.4 g (111% yield inflated by entrained residual solvent) of product as a colorless gum