Synthesis and Characterization of Selenium Containing Schiff Bases: The Selenosemicarbazones

Abstract

Background: Many organoselenium compounds are well known for their applications in various fields. However, some of the organoselenium compounds, like selenosemicarbazones, due to difficulties in their synthesis are not much explored. Herein, we present the synthesis and characterization of five different new selenosemicarbazones. Objective: The study aimed to carry out the synthesis and characterization of novel selenosemicarbazones, a type of Schiff bases. Methods: Selenosemicarbazones are synthesized in a single step, i.e., acid-catalyzed condensation reaction between ketones and hydrazine hydrate in the presence of potassium selenocyanate (KSeCN). Results: Butyrophenone, 4-phenyl 2-butanone, 2-acetonaphthone, 4-nitroacetophenone and menthone were reacted with in-situ generated selenosemicarbazide, which led to the formation of respective selenosemicarbazones. These organoselenium derivatives of Schiff bases have been characterized by mass spectrometry, proton, carbon and selenium NMR. Conclusion: The yields of synthesized butyrophenone, 4-phenyl 2-butanone, 2-acetonaphthone, 4- nitroacetophenone, and menthone selenosemicarbazones varied in between 44 to 65%. The synthesis strategy involved one-pot synthesis of selenosemicarbazone without isolation of toxic selenosemicarbazide.