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61.
Pragati R Sharma Shubham Pandey Vineet K Soni Ganpat Choudhary Rakesh K Sharma 《Supramolecular chemistry》2013,25(9):634-644
ABSTRACTThe current study reveals the synthesis of polymer appended Calix[4]amidocrown-5 with specific binding affinity for iodide at ppm-level. The low detection limits are observed via UV-vis and fluorescence spectroscopy. The time-dependent solution and solid-state 127I NMR studies with 18.8 and 19 ppm shifts, indicate a strong sensing nature of resin towards iodide ion. A significant reduction in surface area and pore volume with higher thermostability of resin after iodide uptake indicated iodide inclusion in the amidocrown cavity. The mechanism of iodide sensing may be governed by noncovalent interactions of NH and OH protons present in amidocrown and phenyl ring as observed in terms of emission enhancement in fluorescence spectroscopy. The binding affinity and stoichiometric determinations are determined by Benesi-Hildebrand and Jobs plots, respectively. 相似文献
62.
Dao M. Nguyen 《合成通讯》2013,43(12):1759-1771
Copper iodide was employed as an efficient catalyst for the synthesis of 1,2,3-triazole derivatives of podocarpic acid at room temperature through “click” chemistry cycloaddition reactions of methyl O-propargylpodocarpate and propargyl O-propargylpodocarpate with azides.
63.
An improved, mild procedure for the CuI‐catalyzed coupling reactions of aryl iodides with aliphatic and aromatic thiols, using L ‐proline as the ligand, is reported. This procedure is noteworthy given its high generality and exceptional level of functional group toleration. 相似文献
64.
Rahman Hosseinzadeh Mahmood Tajbakhsh Maryam Mohadjerani Parizad Rezaei Mohammad Alikarami 《合成通讯》2013,43(17):3023-3031
An efficient synthesis of diaryl ethers by the copper-catalyzed arylation of phenols with a variety of aryl iodide susing KF/Al2O3 as a suitable base and CuI and 1,3 diphenyl-1,3 propandione as the catalyst is described. 相似文献
65.
An ultrasound‐accelerated fast and efficient three‐component reaction for the regioselective synthesis of l,4‐disubstituted 1,2,3‐triazoles using different alkyl and allyl halides, terminal alkynes, and sodium azide in water at room temperature has been developed using CuI as catalyst. Ultrasonication dramatically decreases the reaction times. 相似文献
66.
The reaction of 2-amino-1-(2-propynyl)pyridinium bromide with various iodobenzenes, catalyzed by Pd-Cu, in the presence of sodium lauryl sulfate as the surfactant and cesium carbonate as the base, in water, leads to the formation of 2-substituted imidazo[1,2-α]pyridines. 相似文献
67.
Easily prepared choline iodide is an active catalyst for the synthesis of cyclic carbonates through the coupling reaction of CO2 and epoxides using low pressure (1 MPa), moderate temperature (85 ºC) and green solvents (ethanol and propan-2-ol). The effects of reaction temperature, pressure, reaction time and amount of catalyst used were also investigated. The results showed moderate to high yields and excellent selectivities of cyclic carbonates with vinyl or acrylate groups under mild reaction conditions. The heterogenization of choline over a Merrifield resin gives access to a supported catalyst with good recyclability and reactivity that can be extended to a variety of terminal epoxide substrates. 相似文献
68.
69.
One-pot synthetic strategy has been developed to access isoquinolines and its analogs via Cu-mediated tandem cross-coupling and cyclization in good yields under mild reaction conditions. A mixture of suitably substituted α-bromoaldehyde, terminal alkyne, and aq NH3 in CuI/1,10-phenanathroline catalytic system afforded the 3-substituted isoquinoline regio-selectively in good to excellent yields. 相似文献
70.
Nickel(I) complexes were generated in situ from Ni (PPh3)2Cl2 using activated iron and the complexes combined with N,N′-bis(4-fluorobenzylidene) ethane-1,2-diamine (BFBED) were then used as a catalyst for the 1,4-addition reaction of arylboronic acids to α,β-unsaturated substrates. The reaction proceeded to completion and did not require the addition of a base but the addition of potassium iodide is crucial to this cross-coupling reaction. Moreover, experimental observations suggested a possible Ni(I)–Ni(III) catalytic cycle mechanism. 相似文献