Electrolysis of /V-heterocyclic compounds

In this chapter the electrolysis of V-heterocyclic compounds is discussed the emphasis will be laid on preparative electrolysis, but polarographic results will also be mentioned to supplement the discussion and to suggest further use of preparative electrolysis. Electro-... 

The review on the electrolysis of /V-heterocyclic compounds by Lund in 1970 included a discussion on the polarographic behavior of quinazoline.64 The reduction of quinazoline was complicated by covalent hydration in acidic solution, because the hydrated species were not easily reduced.65 The anhydrous species in alkaline medium were reduced stepwise to dihydro and then to tetrahydroquinazoline, and the dihydro radical intermediate was capable of dimerization, The protonation rates of N-heterocycles in aqueous solution could be determined by polarographic techniques. The rates for quinazoline, and pyrimidine, however, were too fast for measurement which was consistent with predictions from quantum-chemical calculations.66... 

In this Section we shall consider the electrolysis of substituted heterocyclic compounds, where the electrode reaction involves the substituent directly, or when it plays an essential role in determining the course of the reaction. The reductions leading to ring contractions have been discussed in Section IV, and some compounds treated in Section V might well have been included in Section VI. 

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