Theoretical study to synthesis 1,3,5,-tri glycerol benzene using Semiempirical and Ab-Initio calculation methods

الملخص

Theoretical study has been carried out through simulation of synthesis using
quantum methods (semiemprical &Ab-initio ),that’s included in Hyper Chem 6.02 program.
to under standing the Substitution reaction mechanism, and intermediates ,and transition
structures involved during the reactions.
Chemical activity and chemical interaction of reactants and products have been studied
by surface potential energy calculations . estimation of the high probable active sites in
attachment of esterification and alkylations, the energetic properties have been studied ,as
total energy, atomic charge , bond stability bond torsion, electric static field, and heat
formation content.
The probable of first alkylation step has been studied through calculation of total
energy , electric dipole moment constant , and heat change formation . In addition activation
energy barrier calculation of all probable reactions have been carried out steps of the
alkylation reaction.
Thermodynamically of ester hydrolyzed been estimated for 1,3,5,-tri glycerin benzene
,when chemical activity of synthetic compound has been studied through calculation of total
energy ,electrostatic potential, electric dipole moment constant ,atomic charge distribution,
electronic spectrum and heat formation change .
Twenty two of different chemical structure have been suggested and studied ,that’s
represent the most important components of reactions mechanism involved during reactions.
All probable occurrence reactions of substitution reactions were studied . high probable
reactions that is having lowest activation energy value are testing by comparing with other
probable competitive reactions(another probabilities),also the total change in heat content of
reactions has been calculated.
Calculations show that’s , hydroxyl group and hydrogen atom in glycerol molecules of
secondary carbon atom are more active than of primary carbon atom for esterification and
alkylation reactions respectively. glycerol react efficiently with acetic acid in three steps to
produced tri acetate glycerol through endothermic reaction ΔHre = 28.157 kCal mol-1 .
Alkylation reactions at aromatic ring take place through controlling system of
orientation to give up 1,3,5- Tri (glycerol tri acetate) benzene by endothermic reaction Σ
ΔHrea = 8.967(kCal mol^-1 ).

1,3,5- Tri glycerin benzene produced during hydrolysis the ester derivative with nine
mole of water molecule by exothermic reaction ΔHrea = -120.991(kCal mol^-1 ).large electronic
density occurs through new products for nine polar functional gropes of hydroxyl.