Chloroacetaldehyde → HCID 66970903, compound

Participants

Reaction Steps

To a solution of BOC (2R,4S)-2-(aminocarbonothionyl)-4-[(4,4-dimethylcyclohexyl)(2,2-dimethylpropanoyl)amino pyrrolidine (880 mg, 2 mmol) prepared in Step A in dimethoxyethane (10 ml) was added 50 wt % chloroacetaldehyde (0.38 ml, 3 mmol) and NaHCO3 (504 mg, 6 mmol), and stiffed at rt for 2 h. After the reaction finished, the reaction solution was concentrated in vacuo, and extracted with EtOAC. The organic extracts were washed with water and brine, dried over MgSO4, concentrated in vacuo, and the residue was purified by column chromatography (eluent: EtOAc:Hex=1/1). This compound (510 mg, 1.24 mmol) was dissolved in pyridine (0.9 ml, 11.1 mmol), and TFAA (1.0 g, 4.96 mmol) was added dropwise at 0° C. At the same temperature, the solution was stirred for 1.5 h, concentrated in vacuo, and extracted with EtOAc. The organic extracts were washed with 0.5N HCl solution and brine, dried over MgSO4, and concentrated in vacuo. The residue was purified by column chromatography (eluent: EtOAc/Hex=2/1) to give the title compound (249 mg, 51.0%).

Provenance & Evidence