Stereoselective (-specific) synthesis, dynamic 1H NMR and quantum chemical conformational and configurational analysis of norbornene-aziridine--imidoyl system

Stereoselective (-specific) synthesis, dynamic H-1 NMR and computational analysis of -'-{3-azatricyclo[3.2.1.0.(2,4)]oct-3-yl)mesithyloxy)methylene}-1-benzensulfunamide () were investigated. Aziridine nitrogen inversion gives rise to two sets of configurations where the -substituent is S () or () to C7 of the norbornyl ring. At lower temperature, the proton signals of aziridine -- decoalesces to show two conformers and one conformer (-- -- -- ) with ratio of 60:20:20, respectively. Experimentally, the Gibbs free energy of activations [Delta (aEuro) (kcal/mol) +/- A 0.08] were calculated 11.96, 12.45 for isomerizations. The standard Gibbs free energy (Delta (o) kcal/mol) 0.174, 0, 0.174, and 0.298 at 213 K and energy minimum 6.64, 4.77 and 1.78 were calculated for (S) (S), (S) , S isomerizations, respectively. The enthalpy (Delta (aEuro), kcal/mol) and entropy (Delta (aEuro), cal mol(-1) K-1) of activation for the nitrogen inversion of aziridine of were calculated 11.2 and -0.80, respectively.