Phosgene → tert-Butyl N-[6-({7-bromo-15,15-difluoro-4,17,20-trimethyl-3,12-dioxo-13-oxa-4,11-diazatricyclo[14.2.2.16,10]henicosa-1(18),6,8,10 (21),16,19-hexaen-2-yl}amino)isoquinolin-1-yl]-N-[(tert-butoxy)carbonyl]carbamate

Participants

Reaction Conditions

Reaction Steps

To a solution of 4A (289 mg, 0.362 mmol) in dichloromethane (5 mL) and acetonitrile (5.00 mL) at 0° C., was added phosgene (20% in toluene) (0.242 mL, 0.488 mmol). The reaction mixture was stirred at 0° C. for 15 min. Nitrogen was bubbled though the mixture for 0.5 h, then DMPU (˜0.4 mL) was added. The resulting solution was added dropwise via a syringe pump into a solution of TEA (0.353 mL, 2.53 mmol) in dichloromethane (90 mL) at rt over 4 h, stirred for an additional 15 min and then evaporated. The crude product was purified by flash chromatography to give 4B (177 mg, 0.215 mmol, 59.3% yield) as a white solid. MS and 1H NMR are consistent with the desired product.

Provenance & Evidence