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101.
Multi-component synthesis of 2-amino-3,5-dicarbonitrile-6-thio-pyridines has been developed by using the reaction of aldehydes, malononitrile, and thiophenols in the presence of a Zn(II) or a Cd(II) metal-organic framework (MOF) as the heterogeneous catalyst. This protocol tolerates different functional groups on the substrates and does not require the use of any organic solvent. Moreover, the Zn(II) and Cd(II) MOF catalysts can be recovered and reused for a number of runs without loss of activity.  相似文献   
102.
Ionic liquids were found to be a suitable reaction medium for 1,4‐dipolar cycloaddition reactions of an isoquinoline, an activated alkyne, and a 4‐oxo‐4H‐1‐benzopyran‐3‐carboxaldehyde at room temperature to afford [1]benzopyrano‐pyrido‐isoquinoline (=9aH,15H‐benzo[a][1]benzopyrano[2,3‐h]quinolizine) derivatives selectively in good yields. The ionic liquid can be recovered and recycled in further runs without loss of activity.  相似文献   
103.
An efficient and simple method for the synthesis of 2,2-disubstituted-2H-chromenes by one-step cyclocondensation of a phenol with a variety of 1,1-disubstituted propargyl alcohols using BF3·Et2O as the catalyst is described.  相似文献   
104.
An efficient strategy has been developed for the stereo selective synthesis of N-Boc-(2S,3S)-3-hydroxy-2-phenyl piperidine and N-Boc-safingol from benzaldehyde and N-Boc-imine.  相似文献   
105.
The crystal structures of isoxazole, 3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]methyl-5-phenyl-,N-oxide] (C13H13N5O3) (I), isoxazole,3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]-methyl-5-(4-methylphenyl)-,N-oxide] (C14H15N5O3) (II) and isoxazole, 3-[[dihydro-2-[(Z)-2-oxohyrazono]-1H-imidazol-1-(3H)-yl]-methyl-5-(2-methoxyphenyl)-,N-oxide] (C14H15N5O4) (III) have been determined by X-ray diffraction studies. The compound I, crystallized in triclinic space group with unit cell dimensions a = 7.2405(7) ?, b = 7.9936(8) ?, c = 11.6573(11) ?, α = 97.801(2)°, β = 90.884(2)°, γ = 96.250(2)° and Z = 2. Compound II crystallized in orthorhombic space group Pna21 with unit cell dimensions a = 10.1778(10) ?, b = 28.228(3) ?, c = 5.1206(5) ?, and Z = 4. Compound III crystallized in monoclinic space group P21/n with unit cell dimensions a = 7.8439(9) ?, b = 7.8544(9) ?, c = 23.534(3) ?, β = 99.464(2)° and Z = 4. For all three compounds, the five-membered imidazolidine ring adopts an envelope conformation. The crystal structures are stabilized by both the intramolecular N–H···O and intermolecular N–H···N hydrogen bonding.  相似文献   
106.
Russian Journal of Organic Chemistry - A series of N-[2-(4-methoxyanilino)-5-(3,4,5-trimethoxyphenyl)pyridin-3-yl]benzamides have been synthesized, and their structure was confirmed by 1H and 13C...  相似文献   
107.
Molecular Diversity - Diphenyl ether derivatives inhibit mycobacterial cell wall synthesis by inhibiting an enzyme, enoyl-acyl carrier protein reductase (InhA), which catalyses the last step in the...  相似文献   
108.
In the simulation of non-linear free surface flows in a finite domain a major concern is with the radiation condition to be applied at the ‘open’ boundary. No general theoretical radiation conditions are known to exist. In this paper a new open boundary condition is formulated based on energy flux equalization between the non-linear inner domain and a linear outer domain. The non-linear flow in the inner domain is solved numerically using a semi-Lagrangian procedure. The energy flux arriving at the open boundary is removed using a new open boundary condition which acts as a linear wave absorber. For the cases studied the performance of this boundary condition is found to be quite good.  相似文献   
109.
110.
It has been shown that a study of correlation between the average rapidity, 〈y〉, and transverse energy,E T , can be used to distinguish between different origins of large transverse energy events observed inp-Pb scattering in the HELIOS experiment. If the largeE T events are to be attributed to a nuclear dependence of structure functions then the hard scattering picture implies a positive correlation among the above two quantities, contrary to that seen in experiment.  相似文献   
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