الفهرس 
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Abstract
The present entitled thesis “Reaction of 1-substituted -2,4-dinitronaphthalene with
amino acids and amines” comprises four chapters:
The first chapter covers the literature survey on the important publications of different
types of nucleophilic aromatic substitution reactions. The survey also includes the effect
of substrate, solvent, nucleophile and leaving groups on the mechanism of nucleophilic
aromatic substitution reactions. The aim of the present thesis is also included in this
chapter.
The second chapter is devoted to the experimental part of this investigation. The
preparations of the target compounds and purification of solvent are included. Different
spectral measurements such as UV-Vis, IR, 1H-NMR, 13C-NMR and mass spectra were
used to assign the structure of prepared compounds. The equations used for determination
of the reaction rates and calculation of activation parameters: energy of activation (Ea),
Enthalpy of activation (ΔH#), entropy of activation (ΔS#) and free energy of activation
(ΔG#) were also shown.
The third chapter includes the results of the present work that collected in tables and
presented in figures. The fourth chapter involves the discussion for the results obtained.
This chapter is divided into two parts, the first part explains the synthesis of aryl 2,4-
dinitro-1-naphthyl sulfides (4a-i) starting from1-naphthol by nitration to give 2,4-dinitro-
1-naphthol (1) which then undergoes substitution of hydroxyl group by chlorine atom to
yield 1-chloro-2,4-dinitronaphthalene (2). The target thioether compounds (4a-i) are
prepared by the reaction of arythiol (3) with 1-chloro-2,4-dinitronaphthalene (2) in
presence of a base, Equation (4.2). Identification of the reaction products (4a-i) using
different spectroscopic methods are used, namely IR which showed a strong absorption
bands for asymmetric and symmetric stretching of NO2 at 1529-1516 cm-1 and 1374-1344
cm-1, respectively. Moreover, the (C-S-C) showed two medium intensity bands at 773-738
cm-1 and 697-675 cm-1 due to the asymmetric and symmetric stretching vibrational modes,
respectively. Confirmation the structure of the prepared thioether compounds (4a-i) is the
1H-NMR spectra that show the naphthyl protons as well as the phenyl protons and for
compounds 4g, 4h and 4i have singlet signal for CH3 group.
a, X=H; b, X=4-NO2; c, X=4-F; d, X=3-Cl; e, X=4-Cl; f, X=4-Br; g, X=3-OCH3; h, X=4-
CH3;i, X=4-OCH3
Equation (4.2): Synthesis of aryl 2,4-dinitro-1-naphthyl sulfides (4a-i)
English Summary
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The reaction of compounds (4a-i) with hydrazine hydrate gives products depending on
the molar ratio, in case 1:1 molar ratio 1-hydrazino-2,4-dinitronaphthalene (5) is obtained
while the use of molar ratio 1: 100 for substrate (4a-i) and hydrazine hydrate respectively
gives 5-nitro-3H-naphtho[1,2-d]-1,2,3-triazol-3-ol (6), Equation (4.3). Both products are
isolated and identified by different spectroscopic techniques.
Equation (4.3): Reaction of (4a-i) with different ratio of hydrazine hydrate.
UV kinetic studies for the reaction of aryl 2,4-dinitro-1-naphthyl sulfides (4a-i) with
hydrazine hydrate in methanol at different temperatures shows that the reaction is first
order in the substrate (4a-i) and first order in hydrazine hydrate with overall second order
rate constant and so the reaction moves by uncatalyzed pathway. The kinetics of
hydrazinolysis of the naphthyl aryl sulfides (4a-i) are followed spectrophotometrically at λ
= 515 nm corresponding to the formation of 1-hydrazino-2,4-dinitronaphthalene anion
(5a). Table (4.4). It reveals that electron withdrawing substituent enhances the reactivity
while electron releasing substituent inhibit the rate and showed that the effect of
substituents follows the order: 4-NO2 > 4-F > 3-Cl > 4-Cl > 4-Br > 3-OCH3 > H > 4-CH3
> 4-OCH3.
The enthalpy of activation ΔH#, the entropy of activation ΔS# and the free energy of
activation ΔG# for the reaction of hydrazine with thioaryl ether (4a-i) are calculated. The
trends in variation of the activation parameters are quite equal and show a regular
variation with substituents in 4- and 3-position in the leaving group moiety, electron
donating substituents increase and electron withdrawing groups decrease ΔH#. The
entropies of activations ΔS# are negative (66.85-68.16 cal mol-1K-1) suggesting that the
transition state is more ordered than reactants. The almost equal ΔS# values means that the
effect of substituent on ΔS# values is insignificant and points out that the reaction is
enthalpic controlled. Good linear relationship between the entropy of activation (ΔS#) and
the enthalpy of activation (ΔH#) has been observed using the Leffler’s equation ΔH# =
ΔH0 + βΔS#. The slope is the isokinetic temperature, ‘β’ which is 1382 K (r = 0.927),
which it is higher than the experimental temperature (298 - 318K) indicating.