Diethylamine → 5-Methoxy-9-oxo-9H-xanthene-3-carboxylic acid diethylamide

Participants

Reaction Steps

To a solution of 5-methoxy-9-oxo-9H-xanthene-3-carboxylic acid, 3c (6.8 g, 25.2 mmol) in DMF (70 mL), were added HBTU (10 g, 26.4 mmol) and N,N-diisopropyl-N-ethylamine (5.27 mL, 30.2 mmol). The mixture was stirred for 15 min at rt. N,N-Diethylamine (3.12 mL, 30.2 mmol) was added, and the mixture was stirred for 4 h at rt. The mixture was poured into ice-water (300 mL), and a solid precipitated. The solid was separated via filtration, washed with H2O, and air-dried. The solid was purified via flash column chromatography (eluent gradient: 1% MeOH in CH2Cl2 to 5% MeOH in CH2Cl2) to yield 7.93 g (96.7%) of title compound 5-methoxy-9-oxo-9H-xanthene-3-carboxylic acid diethylamide, 4c. MS m/z=326.0 (MH+).

Provenance & Evidence