Pyridine → HCID 90423774, compound

Participants

Reaction Steps

Slowly add trichloromethyl chloroformate (5.80 mL; 2.0 equiv; 48.35 mmoles) over 15 minutes to a 0° C. solution of (2R)-1-[tert-butyl(diphenyl)silyl]oxy-3-imidazol-1-yl-propan-2-ol (9.2 g; 1.0 equiv; 24.17 mmoles) and pyridine (15.64 mL; 8 equiv; 193.40 mmoles) in acetonitrile (450 mL). Stir for 1 hour and then allow the solution to warm to ambient temperature over 1 hour. Add water (30 mL) and concentrate the reaction mixture. Add dichloromethane (50 mL), and slowly pour the resulting solution into 50% saturated sodium bicarbonate (200 mL). Separate the layers and further extract the aqueous layer with dichloromethane (3×150 mL). Dry the combined organic extracts over magnesium sulfate, filter, and concentrate. Purification by column chromatography (10% to 100% ethyl acetate in hexanes) affords the desired (6R)-6-[[tert-butyl(diphenyl)silyl]oxymethyl]-5,6-dihydroimidazo[2,1-c][1,4]oxazin-8-one (5.50 g; 56%). MS (m/z): 407(M+1).

Provenance & Evidence