Synthesis, crystal structure and DFT studies of 3,4-bis-(2-chloro-phenyl)-2-oxa-bicyclo [2.2.1] heptan-6-one

Crystal structure, spectroscopic and theoretical studies on two Schiff base compounds of 2,6-dichlorobenzylidene-2,4-dichloroaniline and 2,4-dichlorobenzylidene-2,4-dichloroaniline

“…We used Gaussian 98 at the NMR shift calculation [16][17][18][19]. Also, geometry optimization and NBO analysis [20] in the gas phase for molecules were performed. The relative energies (∆E), enthalpies (∆H), free energies (∆G), entropies (∆S) and CV of molecules were carried out in gas phase [21].…”

Experimental and theoretical studies of the products of addition–elimination reactions between benzil dihydrazone and three isomeric chlorobenzaldehydes

“…As a consequence, the HOMO-LUMO (HUMO is the highest occupied molecular orbital and LUMO is the lowest unoccupied molecular orbital) energy gaps (ÁE) of the Schiff bases play a more important role (Table 4), for the differences of ÁE (ÁÁE) are significant (34.47 to 52.75 kJ mol À1 ). As we know, the HOMO-LUMO energy separation can be used as an indicator of the kinetic stability of a molecule (Chattopadhyay et al, 2009;Hazra et al, 2009;Das et al, 2011), and it is reasonable to deduce that the differences in the HOMO-LUMO energy separations between similar compounds can be used as an indicator of the relative kinetic stability of the molecules. It can be seen from (a) The molecular structure of BDHOCB, showing the atom-labelling scheme, with displacement ellipsoids for non-H atoms drawn at the 30% probability level at 298 K. (b) The infinite one-dimensional chain of BDHOCB formed through C-HÁ Á ÁCl hydrogen bonds (purple dotted lines), viewed perpendicular to the chain direction, i.e.…”