A new, convenient, benign procedure for the one-step synthesis of unsymmetrical azines by reaction of aromatic aldehyde derivatives and hydrazine sulfate in triethylamine and absolute ethanol solution is presented. This methodology is more useful than the well-known two-step variant (involving preparation of a hydrazone and subsequent reaction with an aldehyde), because it enables the formation of unsymmetrical azines in a one-pot and rapid method without formation of any by-product or without requirement to separate the hydrazone intermediate. The mildness, selectivity, short reaction time, easy work-up, and applicability for large-scale reactions are the main advantages of this protocol for the synthesis of unsymmetrical azine derivatives. Structures of all new compounds were elucidated by 1H and 13C NMR, IR, MS, and CHN measurements.
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