Abstract Efficient syntheses of a variety of so far not accessible, monosubstituted or vicinally disubstituted 1, 2-diazine derivatives are presented. The versatility of these compounds for syntheses of various polyaza bicyclic and tricyclic systems is demonstrated. In addition, a series of surprising reactivities observed (including ring contraction, dismutation, tele- substitution, intramolecular S N-reactions etc.) are discussed.
