VOLUME 5, NO3, SEPT 1983
12
 
SYNTHESIS AND REACTIONS OF SOME ACYLAZIDES BEARING PHOSPHORUS SUBSTITUENTS

S. EL HAMSHARY ,M El-DEEK ,A I HASHEM ,M A HASSAN ,

P-(Diphenylphosphino) benzoyl azide (IIa) and diphenylphosphinoacetyl azide (IIb) are prepared by the action of NaNO2 and HCl on the corresponding acid hydrazides (I). The azides (II) are subjected to both base and acid-catalyzed decompositions. II reacts with hydrazine hydrate to give the precursor acid hydrazides (I). The reaction of (II) with benzylamine affords the corresponding amides (III). When (II) is allowed to react with anhydrous AlCl3 in benzene, toluene or anisole, the corresponding amilides (IV) are obtained. The structures of the products are discussed in the light of their chemical and spectroscopic properties.
Pages(151)
Download
EFFECT OF TEMPERATURE UPON VISCOSITY OF MICELLES IN DIFFERENT SELECTIVE SOLVENTS

MOHAMMAD SAEED ,MUSA KALEEM BALOCH ,NOOR AHMAD ,

Phenomenon of micellization of block copolymers in nine different selective solvents is studied. For this purpose the purpose the viscosity of the micelles in different concentrations and at different (278.16-333.16oK) temperatures is determined. By considering the change of Huggins constant and intrinsic viscosity with the change in temperature, it is concluded that the micelles are more compact at lower temperatures. They expand as the temperature is raised. At higher temperatures the solvent can not hold the molecules together and these micelles change to unimers. One maxima is observed, when the intrinsic viscosity was plotted against temperature. This may be due to the phenomenon stated above.
Pages(155)
Download
OXIDATION OF AMINES: PART I OXIDATION OF AROMATIC PRIMARY AMINES WITH SILVER (I)

IMRAN HAYAT ,MUHAMMAD ZAFAR IQBAL ,

The oxidation of aromatic primary amines was studied in natural, basic or acidic medium catalysed by silver(I). Various aromatic amines could be oxidized to corresponding azoderivatives. Electron withdrawing substituents were found to slow down the reaction and strong substituents did not allow the reaction to proceed. The presence of electron donating substituents such as –CH3 on aromatic amines enhanced the rate of reaction of higher yields of the products were obtained. The reactions were carried out at room temperature. Based on these observations, a mechanism for the oxidation of aromatic primary amines in presence of Ag(I) is proposed.
Pages(159)
Download
THE RAMAN AND INFRA-RED STUDIES OF POLYCRYSTALLINE POTASSIUM DICYANOCUPRATE AT ROOM AND LOW TEMPERATURE

S U QURESHI ,B M CHADWICK ,D A LONG ,

The infra-red and Raman spectra of KCu(CN)2 have been assigned in terms of the known structure. There are no coincidences, and in the CuC stretching and CuCn bending regions there is evidence of factor group splittings at room temperature. On cooling the solid to 15oK there is no evidence of a phase change, but there is significant increase in the signal-to-noise ratio which allows confirmation of the assignments made from room temperature data. Assignments were made for the four components of eight out of the ten fundamentals. No assignments were possible for V4, the totally symmetric CCuC bending vibration and V10, the interionic CuN stretching vibration.
Pages(163)
Download
1H NMR STUDIES OF SOME HETEROCYCLIC COMPOUNDS PART-III. TAUTOMERISM IN 1,2,3 BENZOTRIAZOLE

MANSOOR AHMAD ,L PHILLIPS ,

The exchange of the NH proton in 1,2,3, benzotriazole has been studied by total line shape analysis of 1H NMR spectra. The rates of this process have been found to be dependant on concentration, temperature and the presence of water. The activation parameters (Ea, D*H, D*S, D*G298) for this rate process have been determined.
Pages(171)
Download
1H NMR STUDIES OF SOME HETEROCYCLIC COMPOUND PART-IV. TAUTOMERISM IN 5,6-DIMETHYL-1,2,3-BENZOTRIAZOLE

L PHILLIPS ,MANSOOR AHMAD ,

The exchange of the NH in 5,6-dimethyl 1,2,3-benzotriazole has been studied by total line shape analysis of 1H nmr spectra. It has been observed that the rate of the process is dependent on concentration, temperature, and the water present in solvent as impurity. The activation parameters (Ea, D*H, D*S, D*G298) for the title compound have been obtained.
Pages(179)
Download
INDIRECT DETERMINATION OF SULPHIDE AND SULPHITE BASED ON THE FORMATION OF 2,3,5,6-TETRAKIS (2-PYRIDYL) PYRAZINE IRON (II)-COMPLEX

R B BOZDAR ,M Y KHUHAWAR ,F C NACHNANI ,

An indirect spectrophotometric method for the separate determination of sulphide and sulphite in aqueous solution in described. Iron (III) in slightly acidic medium is reduced to iron (II), to form an intense purple colour of the bis 2,3,5,6 tetrakis (2-pyridyl) pyrazine iron (II) complex. The colour formation of the complex obeys the Beer’s law over the range of 6 x 10-6 to 4.8 x 10-5 sulphide and 2 x 10-5 to 1.6 x 10-4 sulphite ion concentrations. The effect of diverse ions on the determination of sulphide is also evaluated.
Pages(187)
Download
NATURAL LIPIDS FROM EUPHORBIA HELIOSCOPIA LINN

MUHAMMAD KHURSHID BHATTY ,SHAFIQ AHMAD KHAN ,MUHAMMAD NAZIR ,

The natural lipids were extracted with hexane in 2.8% yield and resolved into an acidic fraction (28.7%) and a neutral fraction (71.1%). The normal monocarboxylic acids (19.26%), the hydrocarbons (9.94%), the monohydric alcohols (35.53%) and the sterols (5.61%) were isolated from the acidic fraction and neutral fraction by column chromatography. The class compounds were analysed by gas liquid chromatography, Saturated and unsaturated fatty acids ranging from lauric (C12) to cerotic (C26) were present with palmitic acid (C16) being predominant. The n-alkanes range from henocosane (C21) to heptatriacontane (C37) with hentriacontane (C31) as the major product. The n-alkanols range from behenyl (C22) to myricyl (C30) with ceryl (C26) as the maximum, b-Sitosterol was found to be the major component (97.35%) of the sterol fraction.
Pages(191)
Download
STUDIES ON THE CONDENSATION PRODUCTS OF 1,3-DIARYL-2-PROPEN-1-ONE WITH ETHYL CYANOACETATE

M EL-MOBAYAD ,G H SAYED ,S EL-NAGDY ,

Michael condensation of 3’,4’-dimethylbenzalacetophenone (I) with ethyl cyanoacetate in the presence of ammonium acetate leads to the formation of 6-(3,4-dimethylphenyl)-2-hydroxy 4-phenyl nicotinonitrile (II), 6-(3,4-dimethylphenyl-1,2-dihydro-4-phenyl-2-oxonicotinonitrile (III) and ethyl 2-amino-6-(3,4-dimethylphenyl)-4-phenyl nicotinate (IV). The reaction of II with alkyl halides, phosphorus oxychloride and Grignard reagents gives the 2-alkoxy-(VI)-, 2-chloro-(VII)- and the 3—acyl-(IX)-derivatives. Reactions of VII with amines and hydrazine hydrate, IXb with hydrazine hydrate, hydroxylamine hydrochloride and thiourea, III with ethyl bromoacetate, phosphorus oxychloride, and Grignard reagent and IV with acetyl chloride are described.
Pages(195)
Download
DETERMINATION OF THE BINDING CONSTANTS, BOUND CHEMICAL SHIFTS, AND STOICHIOMETRY OF LANTHANIDE-SUBSTRATE COMPLEXES

IBRAHIM M AL-NAJJAR ,SALIM S AL-SHOWIMAN ,HASSAN B AMIN ,

Analysis of the experimental results of the equilibrium between a lanthanide shift reagent, L, and a substrate, S, is presented. When different methods were used, evaluation of equilibrium binding constants (KB), bound chemical shift (DB), and stoichiometry (n) of lanthanide (L)-substrate (S) complexes brought about the same numerical values under the conditions of [S]o> [L]o. Finally, it is shown that the association between the lanthanide and the substrate (i.e. 1-(X-benzo [b] thienyl-ethylacetate derivatives) has 1:1 stoichiometry.
Pages(201)
Download
12

 

Browse By Issue