Pyridine → tert-butyl 3-(6-amino-8-oxo-7-(4-phenoxyphenyl)-7H-purin-9(8H)-yl)phenylcarbamate

Participants

Reaction Conditions

Reaction Steps

To a stirred mixture of tert-butyl 3-(6-amino-8-oxo-7H-purin-9(8H)-yl)phenylcarbamate (5) (600 mg, 1.8 mmol) and 400 mg 4 Å MS in 16 mL dry DMF were added 4-phenoxyphenylboronic acid (1.05 g, 4.9 mmol), Cu(OAc)2 (320 mg, 1.8 mmol) and pyridine (1 mL, 12.7 mmol). The reaction mixture was heated at 37° C. for 5 hrs under an O2 atmosphere. After cooling down to rt, the reaction mixture was filtered through a Celite pad. The filtrate was diluted with water (100 mL) and extracted with EtOAc (50 mL×3). The combined organic layer was washed with water (100 mL×2) and brine (100 mL×1), dried over Na2SO4, then concentrated to dryness. The residue was purified by column chromatography (silica gel, 0 to 5% methanol in DCM) to give tert-butyl 3-(6-amino-8-oxo-7-(4-phenoxyphenyl)-7H-purin-9(8H)-yl)phenylcarbamate (6) (404 mg, 45%) as a brown solid. LC-MS (ESI): m/z (M+1) 511.

Provenance & Evidence