反应详情

To a solution of (2S,5S)-1-tert-butyl 2-ethyl 5-methylpyrrolidine-1,2-dicarboxylate (6.46 g, 25.1 mmol) in ethanol (20 mL) was added lithium hydroxide mono hydrate (2.11 g, 50.2 mmol) and deionized water (12 mL). The mixture was allowed to stir for 16 hours then partitioned between ethylacetate and a 1:1 mixture of saturated brine and 1N HCl. The aqueous layer was extracted an additional time with ethyl acetate. The organic layers were combined, dried with sodium sulfate and the solvent was removed in vacuo to yield (2S,55)-1-(tert-butoxycarbonyl)-5-methylpyrrolidine-2-carboxylic acid as a white solid (quant.) and was used directly in the following step.

1. customthen partitioned between ethylacetate
2. additiona 1:1 mixture of saturated brine and 1N HCl
3. extractionThe aqueous layer was extracted an additional time with ethyl acetate
4. dry with materialdried with sodium sulfate
5. customthe solvent was removed in vacuo