فهرست مطالب
Iranian Journal of Chemistry and Chemical Engineering
Volume:19 Issue: 1, May-Jun 2000
- 46 صفحه،
- تاریخ انتشار: 1379/10/12
- تعداد عناوین: 10
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Page 1Formation of the molecular complexes between meso-tetraphenylporphyrin(TPP) and the p-acceptors 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) and tetra-cyanoethylene (TCNE) in chloroform solution was investigated spectrophotometrically.The formation constants of the resulting 1:1 molecular complexes were determined usingthe Benesi-Hildebrand and Nash methods. The TPP-DDQ proved to be more stable thanTPP-TCNE complex. The resulting molecular complexes were isolated in crystalline formand characterized.
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Page 6Some new macrocyclic dibenzotetraoxadiamides, tribenzotetraoxadiamides,tribenzopentaoxadiamide, tribenzohexaoxadiamide, and tetrabenzoheptaoxadiamide 15-22 have been prepared. These compounds were obtained in the macrocyclization step byreacting the diamines 6 and 7 with appropriate dicarboxylic acid dichlorides 8-14. Thecyclization does not require high dilution techniques or template effect and provides theexpected dilactams in high yields ranging from 63% to 81%.
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Page 13FT-Raman spectra of saffron (crocus sativus L.) with a partial assign-ment is reported. Based on the Raman data, it is concluded that main pigments insaffron are crocins and crocetin. It is proposed that the quickly attainable FT-Ramanspectrum of solid saffron, may be used as a means of saffron standardization.
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Page 16The cycloaddition reaction of diphenylnitrilimine on the 1,5-benzodiazepineshas been studied. New molecules of triazolobenzodiazepines type have been isolated andcharacterized.
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Page 19The reaction between Ni(II), Co(II), Cr(III) nitrates, Ni(II) chloride andambidentate a-keto ylide benzoylmethylenetriphenylphosphine (BPPY) resulted in isolationof [Ni(BPPY)2](NO3)2. 2H2O, [Ni(BPPY)2]Cl2, [Co(BPPY)2](NO3)2 and [Cr(BPPY)3]-(NO3)3; 2H2O. The compounds were characterized by elemental analyses and infrared 1HNMR spectroscopy, molar conductivity in solution and molecular weight measurements.
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Page 24A phosgene-free synthesis of symmetrical N,N-disubstituted ureas by thereaction of aromatic and aliphatic primary amines and urea promoted by microwaveirradiation in the presence of a suitable energy-transfer solvent such as N,N-dimethyl-acetamide is described.
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Page 291H NMR spectra of a series of enaminones R-CO-CH=C (NHCH2Ph) -R[1, R=CH3; 2, R=C6H5; 3, R=CF3; 4, R=CH2CH2CH2; 5, R=CH2C (CH3) 2CH2], were obtained in the presence of trifluoroacetic acid in CDCl3 or DMSO-d6 at 28ـC. Steric, solvent, electronic and hydrogen bonding effects on the rates of acid-catalyzed NHproton exchanges were investigated. Rate constants were calculated by the 1H NMR lineshape analysis.
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Page 32The facile and high yield synthesis of a new series of dibenzophenones in the presence of polyphosphoric acid (PPA) together with their cyclization to corresponding mono- and dixanthones are described. The aromatic nucleophilic substitution of these new compounds are also studied.
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Page 40Simultaneous thermal analysis (STA) method has been applied to studydecomposition reactions of AP under a flowing nitrogen atmosphere and static air.Results obtained indicate that a phase transformation occurs prior to the decompositionreaction. Decomposition takes place exothermally in two stages, first stage ofdecomposition could be suppressed by the controlled heating programme. Addition of asmall amount of boron lowered the temperature of the exotherm and increased theoverall enthalpy of reactions.
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