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51.
Optimized structures and photophysical properties of mer- and fac-Alq3 have been generated by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT). Investigating the substitution effect in the Alq3 derivatives, the role of the electron-donating (CH3- and NH2-) and electron-withdrawing (F-, CN-, NO2- and phenyl-) groups with 2- to 7-substitution have been analyzed. According to the calculation results, the 4- and 5- substituted Alq3 exhibit an apparent spectral shift relative to the non-substituted Alq3. The HOMO, LUMO, Eg (the energy gap between LUMO and HOMO), (maximum absorption wavelength) and f (the relative oscillator strength) of mer-Alq3 with the 4- or 5-phenyl substitution on the quinoline ligand in the ground electronic state were calculated by using the DFT/B3LYP/6-31G(d) and TD-DFT methods. 5-phenyl substituted mer-Alq3 with an electron-donating substituent showed an increase in the π-delocalization as compared to the 4-phenyl substituted mer-Alq3 derivatives. Similarly, 4-phenyl substituted mer-Alq3 with electron-withdrawing substituents also exhibits increased π-delocalization in the pyridine ring as compared to the non-substituted Alq3. Replacing the CH group at the 4, 5 and 4,5 positions of the quinoline ligand of mer-Alq3 with the aza group (nitrogen atom) gives three Alq3 analogous: AlX3, Al(NQ)3 and Al(NX)3; the calculated energy gap Eg of these derivatives decreases in the order Al(NQ)3>Al(NX)3>AX3. Four quinoline with group III metals Mq3 complexes were investigated for the photophysical properties; the calculated energy gap Eg decreases in the order Tlq3>Inq3>Gaq3>Alq3. The photophysical properties of 4-hydroxy-8-methyl-1,5-naphthyridine (mND) chelated with group III metals (MmND3 complexes) were investigated also; their calculated Eg have the opposite order as those of Mq3 complexes. 相似文献
52.
用N 取代三氯乙酰胺与 3 甲基苯甲酰肼反应 ,合成了 6个新的N 芳基 N’ 芳酰基氨基脲。其结构经元素分析、IR和1HNMR证实。生物活性测试结果表明 ,它们中除 2个化合物外均具有一定的除草活性。 相似文献
53.
54.
I. B. Dzvinchuk S. A. Kartashov A. V. Vypirailenko U. Doller M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2004,40(5):570-574
The possibility has been studied of converting quaternary 3-anilino-1,5-dimethylpyrazolium salts into 3-anilino-1,5-dimethylpyrazole, the first representative of the 1-alkyl-3-arylaminopyrazoles. The dependence of the reaction direction on the nature of the substituent at position 2 has been clarified. The most effective result was obtained with a cyanoethyl substituent. On boiling the initial salt with aqueous ammonia the target product is isolated in quantitative yield. Syntheses of the initial salts are described. C-Sulfonation was detected on interacting 3-anilino-1-benzoyl-3-methylpyrazole and dimethyl sulfate, with the formation of p-(3-amino-1,2,5-trimethylpyrazolio)benzenesulfonate. 相似文献
55.
Facile and efficient synthesis of tetrasubstituted 1,4- and 1,6-dihydropyridines (DHPs) has been achieved by employing three-component domino reaction using dimethyl acetylenedicarboxylate (DMAD), aliphatic amines, and α,β-unsaturated aldehyde in the presence of 30 mol % trifluoroacetic acid. Interestingly, regioselectivity for the synthesis of 1,4-dihydropyridines can be increased by using 30 mol % triflic acid. In addition, the synthesis of fused-naphthyridine derivatives has been accomplished involving imino-Diels-Alder reaction by employing 1,4-dihydropyridines, aromatic aldehydes, and aromatic amines. 相似文献
56.
Hafnium(Ⅳ) bis(perfluorooctanesulfonyl)imide complex is found to be an efficient catalyst for the multicomponent condensation ofβ-naphthol,aromatic aldehydes and urea or amides in perfluorodecalin to afford the corresponding substituted amidomethyl naphthols in good yields.The remarkable features of this new procedure are high yields,shorter reaction times, reusability of catalyst and simple work-up procedures. 相似文献
57.
A general method for the preparation of 2‐(N‐Substituted)‐2‐imidazolines and 2‐(N‐Substituted)‐1,4,5,6‐tetrahydropyrimidines is described. These heterocycles can be synthesized from their respective anilines with 2‐chloro‐2‐imidazoline or 2‐chloro‐1,4,5,6‐tetrahydropyrimidine, generated in situ from imidazolidin‐2‐one and tetrahydropyrimidin‐2(1H)‐one activated by dimethyl chlorophosphate, in good to excellent yields. 相似文献
58.
《Journal of Coordination Chemistry》2012,65(6):607-611
A new substituted tetra-(4-octanethiol-5-nitro)phthalocyaninatocopper complex was synthesized by nucleophlic substitution of tetra-(4-bromo-5-nitro)phthalocyaninatocopper where the bromo activated by an ortho-nitro group is easily substituted by 1-octanethiol. 相似文献
59.
《Green Chemistry Letters and Reviews》2013,6(1):73-78
Abstract An efficient synthesis of 3-amino 1H-pyrazoles is described. The reaction of β-keto nitriles with hydrazines in the presence of a catalytic amount of p-toluene sulphonic acid using polyethylene glycol-400 as an efficient and recyclable reaction medium afforded the corresponding 3-amino 1H pyrazoles excellent yields. 相似文献
60.
With the aim of preparing new biologically active compounds a series of N(1)-substituted 5-amino-3-methylpyrazoles has been obtained from -aminocrotononitrile and mono-substituted hydrazines.K. A. Timiryazev Moscow Agricultural Academy, Moscow 127550, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, 342–344, March, 2000. 相似文献