Synthesis and dynamic 1H NMR study around C=C and C-C bonds in a particular phosphorous ylide drived from triethyl phosphite

Stable crystalline phosphorus ylide was obtained in excellent yield, in the presence of phtalimide as a NHheterocyclic compound. This ylide exists in the solution as a mixture of the two isomers at ambient temperature, so dynamic 1H NMR effects were investigated at different temperatures around the carbon-carbon single bond and carbon-carbon double bond in the two Z- and E- rotational isomers. In addition, theoretical studies were performed on the same bonds using ab initio methods at HF/6-31G(d,p) and B3LYP/6-31G(d,p) levels of theory. As a results,HF/6-31G(d,p) level provides better results in comparison with dynamic 1H NMR data.