Three Questionable Cases in the Chemistry of Quinoxalines and Benzodiazepines in the Way of the Syntheses of Benzimidazoles.

The reaction of (I) with Vilsmeier reagent to give (III), the reaction of (V) with aqueous NaOH to give (VI), and the reaction of (X) with o-phenylenediamine to give (XI) are studied and earlier reports are revised.