反应详情

5% Pt/C (Sigma-Aldrich catalog #205931, 0.80 g, 30.2 mmol) was carefully wetted down under argon with ethanol. Acetic acid (5.30 mL, 93 mmol) was added thereto followed by (R)-ethyl 8-(1-phenylethylamino)-1,4-dioxaspiro[4.5]dec-7-ene-7-carboxylate (prepared in a similar manner as that described in International Patent Application No. WO 2005/048932, 10.0 g, 30.2 mmol) in ethanol (50 mL). The reaction was then hydrogenated at 50 psi for about 16 hours with stirring in a Parr Shaker apparatus. The catalyst was carefully filtered under argon and the filtrate concentrated to yield an amber oil. The oil was dissolved in EtOAc then rinsed with 5% Na2HPO4 until pH=8-9 (5 rinses). The EtOAc layer was dried over sodium sulfate and concentrated to give (7S,8R)-ethyl 8-((R)-1-phenylethylamino)-1,4-dioxaspiro[4.5]decane-7-carboxylate (5.40 g, 16.2 mmol, 54% yield) as an amber oil. MS (ESI+)=334.25 (M+H)+.

1. customprepared in a similar manner as
2. filtrationThe catalyst was carefully filtered under argon
3. concentrationthe filtrate concentrated
4. customto yield an amber oil
5. washthen rinsed with 5% Na2HPO4 until pH=8-9 (5 rinses)
6. dry with materialThe EtOAc layer was dried over sodium sulfate
7. concentrationconcentrated