2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → HCID 21109098, compound

Participants

Reaction Steps

A solution of crude ethyl 5-amino-2-methylthio-4-(3-nitro-phenyl)-7,8-dihydro-quinazoline-6-carboxylate (example 27d, 1.19 g) in CH2Cl2 (31 ml) was cooled to 0° C. A solution of DDQ (1.14 g) in toluene (31 ml) was added dropwise, the ice-bath removed and the solution was stirred for an additional 30 min at room temperature. The mixture was diluted with CH2Cl2 (ca 100 ml) and washed with a saturated aqueous solution of NaHCO3 (3×100 ml) and brine (2×50 ml). The combined aqueous layers were back-extracted with CH2Cl2. The combined organic layers were dried (MgSO4) and concentrated under reduced pressure. The title compound was purified by chromatography on silica gel using hept/EtOAc=9/1 to 3/2 (v/v) as eluent.

Provenance & Evidence