VOLUME 14, NO1, MAR 1992
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COMPLEXATION TENDENCY OF 1,3-DISUBSTITUTED HALOPROPANE-2-OLS WITH DIFFERENT BASES - AN IR STUDY

SHAHIDA SHAMIM ,MANSOOR AHMAD ,QADAR SHARIF ,

The proton donor-acceptor complexes formed by 1,3-disubstituted halopropane 2-ols with tetrahydrofuran (THF) and triethylamine (TEA) in carbon tetrachloride solution have been studied. The area of the OH-stretching band corresponding to the intermolecularly H-bonded complexes was plotted against concentration of THF to determine the relative strength of H-bonding. The equlibrium constant and the frequency shifts were calculated. The equilibrium constants for the 1:1 complexes between alcohols and the base are in the order Br < Cl < F.
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DENSITIES AND EXCESS MOLAR VOLUMES OF BINARY AND TERNARY MIXTURES OF ETHANOL .2. HALOETHANOLS AND TRIETHYLAMINE IN CARBONTETRACHLORIDE AND CYCLOHEXANE

SHAHIDA SHAMIM ,MANSOOR AHMAD ,

Densities were determined for the binary and ternary mixture of the alcohols and triethylamine in CCl4 and cyclo-C6H12 at 298 K. From the experimental results, the excess molar volume (VM(E)) were calculated. VM(E) are positive for binary mixtures of the alcohols in both, CCl4 and cyclo-C6H12. But for ternary mixture (in CCl4), the excess molar volumes are negative in the low concentration range of the alcohols. The difference has been explained in terms of interstitial accomodation of the solvent and possible H-bond interaction of the type OH...Cl between the components of the system. Besides, positive excess molar volumes are higher for 2-haloethanols than those for ethanol. These high values have been attributed to the substitution of hydrogen atom by halogen atoms.
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ORGANOCHLORINE PESTICIDE CONTAMINATION OF RAINWATER, DOMESTIC TAP-WATER AND WELL-WATER OF KARACHI-CITY

MOHD SAEED ALAM ,ZAHID BEGUM ,SAEEDAN BEGUM ,

The presence of six organochlorine pesticides has been studied in rain-water, tap-water and underground-water of Karachi. The probable sources of these insecticides in the atmosphere and water arc discussed.
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PREPARATION AND ESR STUDY OF THE COMPLEXES OF L-HISTIDINE WITH ZINC AND CADMIUM

MARGARET GOODGAME ,IZHAR HUSSAIN ,

The preparation of the complexes Zn(Mn) (L-His)2 and Cd(Mn) (L-HiS)2 are reported . The E.S.R. spectra, at both X- and Q-band of Mn(II) ions doped in these complexes and also those of M(L-His)2.2H2O (M = Zn and Cd) are reported, and the zero-field splitting parameters D and (lambda = E/D) are deduced. Considerably higher values of D and lambda observed for M(Mn) (L-His)2.2H2O (M = Zn and Cd) suggest quite appreciable deviation from regular symmetry as would be expected from their crystal structure studies [1-2]. The distinctly lower values of D and lambda observed for anhydrous complexes, M(Mn)(L-His)2 (M - Zn and Cd), suggest geometries tending, most probably, towards regular octahedral structures. The negative sip of D observed from the Q-band spectra of these complexes, suggests that the principal D-tensor axis lies along the line of two Cd-N bonds, and the coordinated oxygens from the carbonyl groups are in cis-positions.
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PREPARATION AND SOME STUDIES OF COPPER(II) AND NICKEL(II) COMPLEXES OF NEW TETRADENTATE SCHIFF-BASES DERIVED FROM BETA-DIAMINOPENTANE

M Y KHUHAWAR ,A G BHATTI ,

The copper(II) and nickel(II) complexes of new tetradentate ligands bis (acetylacetone)ethylmethylethylenediimine (H2AA2EMen), bis(trifluoroacetylacetone)ethylmethylethylenediimine (H2F3AA2EMen) and bis(trifluoroacetylmesityloxide)ethylmethylethylenediimine (H2F3AM2EMen) have been prepared and characterized using IR H-1-NMR and mass spectroscopic techniques. ne reagents and metal complexes have been examined spectrophotometrically and the effects of complexation, solvent and fluorosubstitution on the absorptiometric properties have been reported.
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REACTION OF ASCORBATE WITH DIFFERENT SPECIES OF IRON(III)-3,4,5-TRIHYDROXY BENZOIC-ACID COMPLEX

S ARIF KAZMI ,ZAHIDA T MAQSOOD ,

Different species of Fe(III)-galic (FeHL, FeL2, FeL3) acid complexes are formed at different pH values These species have different rates of reduction with ascorbate. By measuring the overall rates of reduction of Fe(III) to Fe(II) at different pH and using the calculated species distribution at the corresponding pH a graphical procedure was applied to obtain the bimolecular rate constants for reduction of indivudal complex species. These were k(FeHL) = 87.9, k(FeL) = 113 and k(FeL2) = 4 all in units of M-1S-1.
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SOME REACTIONS OF 6-CHLORO-2-METHYL 4H-1-BENZOPYRAN-4-ONE .2.

ASHRAF A AHMED ,MOUNIR A I SALEM ,ALI G EL SHEKEIL ,HASSAN M F MADKOUR ,A S BABAQUI ,

6-Chloro-2-methyl-4-H-1-benzopyran-4-one (1) gave the isoxazole derivative (2a) on reaction with hydroxylamine hydrochloride. The action of hydrazine and phenylhydrazine on (1) resulted in pyrazole derivatives (3a) and (3b) respectively. The reactivity of (1) with ethyloxalate and aromatic nitroso compounds have been investigated. Phthalide (8a) derived from the chromone (1) was synthesised and rearranged easily into 1,3-indandione (9) upon refluxing with alcoholic sodium methoxide. Cleavage of (8) with amines and hydrazine hydrate was studied. Thiation of phthalide (8a) with either Lawesson's re-agent or phosphorous pentasulphide yielded the corresponding thione (8c)
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ORGANOHALOGEN COMPOUNDS .3. THE PREPARATION AND CERTAIN REACTIONS OF CHLOROSUBSTITUTED 2,3-DIMETHYLBUTA-1,3-DIENES

ANTHONY E TIPPING ,ALBERT C PRATT ,MOHAMMAD A BIGDELI ,

The dienes CH2=C(CH2Cl),CMe=CH2 (3), CHCl=CMe.CMe=CH2 (4), CHCl = CMe. CMe = CHCl (14), and CHCl = C(CH2Cl). CMe = CH2 (21) have been synthesised via chlorination of 2,3-dimethylbuta- 1,3-diene. Copper-catalysed addition of benzenesulphonyl chloride to 2,3-dimethylbuta-1,3-diene and diene (3) gives the 1,4-adducts PhSO2. CH2. CMe = CMe. CH2Cl and a mixture of PhSO2.CH2.C(CH2Cl)-CMe.CH2Cl and PhSO2. CH2. CMe = C (CH2Cl)2, respectively. Dehydrochlorination of the former adduct gives the diene PhSO2CH = CMe.CMe = CH2 which polymerises in air. Dienes (4) and (21) form Diels-Alder adducts with tetracyanoethylene. Chlorination of diene (14), is surprisingly accompanied by addition of hydrogen chloride and gives the compounds CHCl2.CClMe.CClMe.CH2Cl and CHCl2.CCl(CH2Cl). CClMe.CH2Cl. The dichloride CH2Cl. CMe = CMe. CH2Cl reacts with an equimolar amount of bromine by addition, but with an excess of bromine the products are CH2Br.C(CH2Cl) = C(CH2Cl).CH2Br(89%) and (CH2Br)2C = C(CH2Cl).CH2Br (6%). Unexpected substitutive bromination is observed on treatment of the trichloride (CH2Cl)2C=CMe.CH2Cl with bromine to give (CH2Cl)2 C = C(CH2Cl).CHzBr (95%).
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ALKYLATION OF AMINES WITH BETA-AROYLACRYLIC ACIDS AND SOME STUDIES ON THE ALKYLATING PRODUCTS

M A SAYED ,

Beta-Aroylacrylic acids (1a-d) react with primary amines and secondary amines to give the corresponding alpha-alkylamino-beta-propionic acids (2a-r) and (3 a-h). Treatment of (2c) and/or (2e) with acetic anhydride gave the butenolide (4) and the ketone (5). Reaction of (4) with phenylhydrazine gave the phenylhydrazone (6). Reaction of (2e) with hydrazine and/or phenylhydrazine gave the pyridazinone derivatives (7a and b).
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SYNTHESIS AND FUNGICIDAL ACTIVITY OF SOME NEW OF 2,4-DICHLOROBENZOIC ACID 5-SULFONYL AMINO-ACID DERIVATIVES

RAGAB A EL SAYED ,M F BADIE ,F A KORA ,N S KHALAF ,

2,4-Dichlorobenzoic acid reacts with chlorosulphonic acid to yield the corresponding sulphonyl chloride (1). Subsequent condensation with nucleophiles afforded sulphonyl derivatives (2-11), which are used for the synthesis of methyl esters (12-18), the corresponding hydrazide (19-22) and the dipeptide derivatives (23-36). The spectral data of the synthesized compounds (2-36) and the results of preliminary biological screeing are briefly discussed
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