1,2-Dicarbonyl compounds, such as benzil, can be characterized by reaction with o-phenylenediamine to form a substituted quinoxaline.

1,2-Dicarbonyl compounds, such as benzil, can be characterized by reaction with o-phenylenediamine to form a substituted quinoxaline.Write the structure for the quinoxaline derivative obtained when benzil is the reactant. Do you think this compound would be coloured? If so, why? Suggest a plausible mechanism for the formation of the quinoxaline compounds based on the reaction scheme shown above.