Triethylamine → Benzyl(3-(benzyloxy)-2-(hydrazinylcarbonyl)-4-oxo-6,7,8,9-tetrahydro-7,10-ethanopyrimido[1,2-a]azepin-10(4H)-yl)carbamate

Participants

Reaction Steps

To a solution of 3-(benzyloxy)-10-(((benzyloxy)carbonyl)amino)-4-oxo-4,6,7,8,9,10-hexahydro-7,10-ethanopyrimido[1,2-a]azepine-2-carboxylic acid, Intermediate 4 (1 g, 2.043 mmol) in CH2Cl2 (20 mL) was added oxalyl chloride (0.286 mL, 3.27 mmol). A few drops of DMF were added and the mixture stirred at room temperature for 2 h. Solvent was then removed under reduced pressure. The crude acid chloride was then diluted with dichloromethane (10 mL)) and added to a stirred solution of hydrazine (0.641 mL, 20.43 mmol) and triethylamine (2.85 mL, 20.43 mmol) in CH2Cl2 (20 mL) and the resulting solution stirred at room temperature. After 16 h the reaction mixture was poured into sat. NaHCO3 and extracted with dichloromethane (50 mL×3), dried (Na2SO4), filtered and concentrated to give a yellow oil which was used in the next step without further purification. LCMS (M+H)=504.10.

Provenance & Evidence