反应详情

A solution of 30.0 g (162 mmol) of N-tert-butyl-3,3-dimethyl-2-oxo-butyramide (D. Seyferth, R. C. Hui, Tetrahedron Lett. 1984, 25, 5251) and 50 g (413 mmol) of (S)-1-phenylethylamine in 150 ml of toluene was boiled under reflux on a water separator for 20 hours. Subsequently, the solvent and excess amine were removed in a vacuum. The residue was treated with 200 ml of hexane at 0° C. and stirred. After filtration of the suspension and concentration in a vacuum the residual oil was distilled. There were obtained 37.2 g (80%) of (S)-N-tert-butyl-3,3-dimethyl-2-(1-phenylethylimino)-butyramide of boiling point 140° C. at 0.3 mbar. [α]=-40.7 (c=1.0, CHCl3).

1. customSubsequently, the solvent and excess amine were removed in a vacuum
2. additionThe residue was treated with 200 ml of hexane at 0° C.
3. filtrationAfter filtration of the suspension and concentration in a vacuum the residual oil
4. distillationwas distilled