Glyoxal → 5,8-Dibromoquinoxaline

Participants

Reaction Steps

A 40% aqueous solution of glyoxal (8.8 M, 6.3 mL, 55.1 mmol, 1.3 equiv) was added to a suspension of 3,6-dibromo-benzene-1,2-diamine (Step 179.6) (11.3 g, 42.4 mmol) in EtOH (280 mL). The reaction mixture was heated to reflux for 3 h and allowed to cool to it overnight. Vacuum filtration of the reaction mixture afforded 9.7 g of the title compound as a yellow solid: APCI-MS: 286/288/291 [M−1]−; tR=4.40 min (System 1).

Provenance & Evidence