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21.
Summary Organometallic compounds of general formula (SCN)2M(NCSeHgR)2 (M=CoII, NiII, R=n-C5H11,i-C5H11) have been prepared. They behave as Lewis acids, forming complexes with pyridine and 2,2-bipyridyl, characterized by elemental analysis, molecular weight, molar conductance, i.r. spectral (4000–200 cm–1), electronic spectral and magnetic susceptibility measurements. The Lewis acids are monomeric with bridging thiocyanate, or selenocyanate between M2+ and Hg2+. Cobalt and nickel acquire tetrahedral and octahedral configurations respectively through axial bridging, whereas mercury retains its linearity. Pyridine links to the metal in the Lewis acid and forms L2(SCN)2M(NCSeHgR)2 complexes. Bipyridyl ruptures the NCX bridge and forms cationic-anionic [M(bipy)3][(NCS)(NCSe)HgR]2 complexes. 相似文献
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Trushant Lohar Sanjay Jadhav Arjun Kumbhar Ananda Mane Rajashri Salunkhe 《Research on Chemical Intermediates》2016,42(6):5329-5338
An environmentally benign, multicomponent integrated chemical process has been developed for the synthesis of 3,5-dispirosubstituted piperidines by cyclo-condensation reaction of amines, formaldehyde, and dimedone using iron(III) trifluroacetate [Fe(F3CCO2)3] Lewis acid in aqueous micellar medium at ambient temperature (25–30 °C). The heterogeneous solid acid catalyst conveniently promotes this double amino methylation reaction in which six molecules condense in one pot to form six new covalent bonds. The synthesized 3,5-dispirosubstituted piperidines have been screened for their in vitro antibacterial activity using agar well method. Many of these compounds showed satisfactory antibacterial activity as compared to standard drugs against all the bacteria tested. 相似文献
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Pyrazolopyrimidine and pyrimidopyrimidine derivatives have shown a wide range of biological activities such as acting as A1 adenosine receptors, kinase insert domain receptor (KDR), Rous sarcoma oncogene (Src), epidermal growth factor receptor (EGFR), antiproliferative, dihydrofolate reductase (DHFR), antimicrobial, antifungal, and lipid peroxidation. Because of this wide range of activities, we have synthesized pyrazolo[3,4‐d]pyrimidines and pyrimido[4,5‐d]pyrimidin‐4‐one derivatives. 相似文献
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Triphenylene derivatives with six peripheral chains can make excellent discotic liquid crystals showing great promise in electronic devices. Vanadium oxytrichloride was found to be a novel reagent for the preparation of various triphenylene derivatives. Symmetrically substituted hexaalkoxytriphenylenes were obtained from o-dialkoxybenzenes by oxidative trimerization with VOCl3 in high yields. Oxidative coupling of a 3,3',4,4'-tetraalkoxybiphenyl with 1,2-dialkoxybenzenes yielded unsymmetrically substituted derivatives of triphenylene; a direct coupling of a 3,3',4,4'-tetraalkoxybiphenyl with alkoxyphenol produced monofunctionalized triphenylenes. 相似文献
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The polymeric coordination compounds have been synthesized using the dipotassium salt of N,N′‐di(carboxymethylene)terephthalaldehydediimine (K2SB1) or N,N′‐di(carboxyethylene)terephthalaldehydediimine (K2SB2) with manganese(II), cobalt(II), nickel(II), copper(II), zinc(II), and cadmium(II). The ligands have been characterized by 1H‐NMR, and 13C‐NMR spectra. The polychelates have been characterized by elemental analyses, magnetic measurements, thermogravimetric analyses, electronic spectra and infrared spectra. The coordination compounds are colored, and the central metal ions are octahedrally coordinated with two water molecules and the Schiff bases. The Schiff bases act as di‐negative tetradentate ligands, in which bonding occurs through two oxygen and two nitrogen atoms. The polymers are insoluble in all common organic solvents such as acetone, methanol, ethanol, N,N‐dimethylformamide and dimethylsulfoxide. 相似文献
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