Study on the reactions of fluoroalkanesulfonyl azides with pyrazine and its derivatives

The thermal reactions of fluoroalkanesulfonyl azides RfSO2N3 with pyrazine and its derivatives are studied in detail. All the reactions involved the fluoroalkanesulfonyl nitrene intermediates RfSO3N: which was captured by pyrazine to give the pyrazinium N-fluoroalkanesulfonyl ylides C4NH4N+–−NSO2Rf and hydrogen abstraction product RfSO2NH2, but no corresponding N-pyrazinyl fluoroalkanesulfonyl amide derivatives RfSO2NHC4N2H3 were isolated. Excess azides did not afford the bisN-ylide product RfSO2N−–+NC4H4N+–−NSO2Rf.