Ethylenediamine → HCID 68702989, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 2,4,6-trimethylbenzenesulfonic acid 3-(4-chlorophenyl)-8-formyl-2-isopropyl-4-oxo-4H-chromen-7-yl ester (141 mg, 0.269 mmol) and ethylene diamine (0.6 ml) in anhydrous pyridine (3.5 ml) in a sealed 5 ml microwave tube is heated under microwave irradiation at 100° C. for 1 h. A further aliquot of ethylene diamine (0.6 ml) is added, and the mixture is heated at 140° C. for 30 min. A further aliquot of ethylene diamine (0.4 ml) is then added, and the mixture is heated at 160° C. for 50 min and finally at 150° C. for 2 h. The mixture is cooled to room temperature, and the volatiles are removed under reduced pressure. The residue is dissolved in dry methanol (4 ml), and the solution is cooled to 0° C. Sodium borohydride (15 mg, 0.4 mmol) is added, and the mixture is stirred for 18 h as it warms to room temperature. The mixture is quenched by the addition of water (30 ml) and extracted with dichloromethane (3×20 ml). The organic phases are combined, washed with saturated brine (50 ml), dried (MgSO4), filtered and evaporated under reduced pressure. The residue is purified by preparative reversed phase chromatography using 90% water/-acetonitrile to 100% acetonitrile as eluant. The pure product-containing fractions are combined and evaporated to dryness, and the residue is triturated with n-hexane containing a small amount of dichloromethane. The resulting colourless powder is recovered by filtration and dried.

Provenance & Evidence