1,2-Dichloroethane → HCID 59753406, compound

Participants

Reaction Conditions

Reaction Steps

15.06 g of N-Boc-(L)-proline (69.96 mmol) and 25.00 g (69.96 mmol) of the serine ester from example 1A are dissolved in methylene chloride (250 ml) under argon. The solution is cooled to −20° C. and treated with 13.41 g of EDC (69.96 mmol) and 0.85 g of DMAP (7.00 mmol). The reaction solution is stirred at −20° C. for 1 h and then at room temperature for 48 h, evaporated and the residue is taken up in ethyl acetate. The solution is washed with aq. citric acid, aq. saturated sodium hydrogen-carbonate solution and aq. saturated sodium chloride solution. The organic phase is dried over sodium sulfate and evaporated. 32.47 g (84% of th.) of product are isolated after silica gel chromatography using toluene/ethyl acetate (5/1).

Provenance & Evidence