Synthesis and dynamic NMR studies of some new symmetrical podands of dithiocarbamates formed from Bis(N-thiazol)chloroacetamides

摘要

Reactions of dithiocarbamates salts (IV_(a-c)) with bis(N-thiazol) chloroacetamides(II_(a,b)) in DMF furnished corresponding podands V _(a-f)as in high to excellent yields. Two reacting ligands (II _(a,b)) were obtained in the reaction of bis(aminothiazoles) (I _(a,b)) with chloroacetyl chloride. Dynamic NMR spectroscopic data of two series of podands (and) are discussed and figured out their free energy of activation (ΔG_c ~≠) at coalescence temperatures. The ΔG_c ~≠s of these podands were attributed to conformational isomerization in the range of 14.9-16.2 kcal/mol due to rotation and resonance effect about thioamide C - N bond.