24576-55-4Relevant academic research and scientific papers
Theoretical study of the cyclization of α-iminothioaldehydes into dihydrothiazoles
Arnaud, Roger,Pelloux-Leon, Nadia,Ripoll, Jean-Louis,Valle, Yannick
, p. 1077 - 1086 (2007/10/02)
When synthesized by retro-Diels-Alder reaction under flash vacuum thermolysis conditions, α-iminothioaldehydes undergo a rearrangement to 2,3-dihydro-1,3-thiazoles.These secondary enamines in turn are transformed into the more stable 2,5-dihydro-1,3-thiazoles upon standing in CDCl3 solution.The route from α-iminothioaldehydes to dihydro-1,3-thiazoles has been studied by ab initio molecular orbital theory.Geometries of stationary points on the potential energy surface were optimized using HF/6-31G(d,p) and MP2/6-31(d,p) calculations.Relative energies wereestimated using MP4STDQ calculations and the 6-31 + G(d,p) basis set and corrected for zero-point vibrational energies.Intrinsic reaction coordinate calculations at HF/6-31G(d,p) level were performed in order to check the profile of the proposed rearrangement.These calculations support the experimental findings.The most energy requiring step was found to be trans -> cis isomerization of the methylimino group -1 at the QCISD(T)/6-31 + G(d,p) level>
