2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → HCID 178468702, compound

Participants

Reaction Conditions

Reaction Steps

To a 250-mL round-bottom flask was placed a solution of ethyl 4-hydroxy-5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidine-6-carboxylate (4.0 g, 14.39 mmol, 1.00 equiv) in 1,4-dioxane (50 mL) was added DDQ (8 g, 35.24 mmol, 2.45 equiv) at room temperature. The resulting solution was stirred for 3 h at 90° C. under nitrogen. After cooling, the reaction was quenched with saturated aqueous Na2CO3. The solids were filtered out and the filtration was extracted with 3×100 mL of dichloromethane. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate and concentrated under vacuum. The residue was applied onto a silica gel column with ethyl acetate/petroleum ether (1:1) to give the resulted ethyl 3-hydroxy-8-thia-4,6-diazatricyclo[7.4.0.0[2,7]]trideca-1(9),2(7),3,5,10,12-hexaene-12-carboxylate (2.2 g, 56%) as a brown solid.

Provenance & Evidence