反应详情

To an ice-cooled solution of (S)-methyl 2-amino-3,3-dimethylbutanoate (0.411 g, 2.262 mmol) in DCM (20 mL) was added N,N-Diisopropylethylamine (1.182 mL, 6.79 mmol). The formed solution was stirred for 5 min before addition of carbonic acid pyridin-2-yl ester 2,2,2-trifluoro-1,1-dimethyl-ethyl ester (1.24 g, 4.98 mmol, from step 1a) in DCM (10 mL). The final light yellow solution was stirred at room temperature overnight. The reaction mixture was washed with 5% citric acid aqueous solution, 0.1 M NaOH aqueous solution, and brine, then dried over Na2SO4, filtered, and evaporated to dryness. The residue was purified by silica gel column, eluted with (4:1) hexane-EtOAc to afford a colorless oil as the product (673 mg, 99%).

1. washThe reaction mixture was washed with 5% citric acid aqueous solution, 0.1 M NaOH aqueous solution, and brine
2. dry with materialdried over Na2SO4
3. filtrationfiltered
4. customevaporated to dryness
5. customThe residue was purified by silica gel column
6. washeluted with (4:1) hexane-EtOAc