Synthesis of some 1,2,3-ThiadiazoleDerivatives

Abstract

Thiadiazole compounds are playing an important role in our life, through their biological activities in various fields, as antibacterial, antifungal, plant activator, and as pesticides. In this work six compounds as 1,2,3-thiadiazole derivatives were prepared. In this work carbonyl groups were allowed to condense with ammonia derivatives of semicarbazide to give imines’ bond. The carbonyl group of semicarbazide acts as a reactive group in cyclization of the reaction product between ketonic compounds of semicarbazide (semicarbazone) with thionyl chloride to give five-membered heterocyclic rings. The compounds were prepared according to a well- established literature methods and the identities of these compounds were confirmed by IR, H1-NMR, and MS Spectrometer and T.L.C. analysis. Mechanism of reaction and appropriate retro synthetic analysis were given and discussed in chapter three. Detailed spectral (IR, H1-NMR, MS) analysis of the target compounds was given. The functional groups and protons environment were assigned to the proper absorption bonds, special emphasis was put upon the carbonyl group stretching vibration in IR. A variation in the number of peaks, positions and increasing or decreasing in the values of bonds were noticed according to the various effects, such as resonance effects, conjugation effects and anisotropic effects.