Phosgene → tert-Butyl N-[(tert-butoxy)carbonyl]-N-(6-{[(2R,15R)-7-(cyclopropanesulfonyl)-18-fluoro-20-methoxy-4,15-dimethyl-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}-7-fluoroisoquinolin-1-yl)carbamate

Participants

Reaction Steps

Phosgene (87 mg, 0.176 mmol) was added dropwise to a solution of 25D (148 mg, 0.176 mmol) in acetonitrile (2.5 mL)/CH2Cl2 (2.5 mL) at 0° C. The mixture was stirred at rt for 30 min. Ar was bubbled though the solution (10 min) to remove excess phosgene, and then the mixture was added to a solution of TEA (0.123 mL, 0.881 mmol) in CH2Cl2 (25 mL) at 40° C. over 5 h. The reaction was stirred at rt overnight, quenched with H2O (1 mL) and MeOH (5 mL) and then concentrated. The crude product was purified by flash chromatography (loading in chloroform, 0% to 100% ethyl acetate in hexane over 15 min using a 12 g silica gel cartridge). The diastereomers were separated by a prep chiral HPLC (R,R-Whelk-O column 21.1×250 mm) to give 25E (20 mg, 0.023 mmol, 13.11% yield).

Provenance & Evidence