نتایج جستجو برای: boron trifluoride
تعداد نتایج: 18208 فیلتر نتایج به سال:
A highly efficient method for the oxidation of aldehydes to carboxylic acids using PolyVinylPolyPyrrolidone supported - Boron Trifluoride (PVPP-BF3) in the presence of 35% hydrogen peroxide has been developed in acetonitrile at 60 °C. This procedure cleanly oxidizes variety of aldehydes to the corresponding carboxylic acids. Oxidative esterification of benzaldeh...
A series of artemisinin (1) derivatives containing bromo and heterocyclic or aromatic amine functions was prepared in the search for analogues with good water solubility and high antimalarial activity. Treatment of dihydroartemisinin (2a) with boron trifluoride etherate at room temperature gave the key intermediate, 9,10-dehydrodihydroartemisinin (3), which, on reaction with bromine, gave the d...
hexane was shaken with 2 ml. of boron trifluoride etherate, BF3 + (C2H6)20 (b.-p. 124-126°), at room temperature. The dark blue complex was decomposed by the addition of 100-200 ml. of 95% methanol, then transferred with water into hexane. The hypophase was discarded and the epiphase washed, dried, adsorbed on a suitable lime-celite column (2:1) and developed with hexane. The respective zones w...
Lewis acids have recently been recognized as catalysts enabling enantioselective photochemical transformations. Mechanistic studies on these systems are however rare, either due to their absorption at wavelengths shorter than 260 nm, or the limitations of theoretical dynamic for larger complexes. In this work, we overcome challenges and employ sub-30-fs transient in UV, combination with a highl...
Two new pyrrolylquinoline-substituted heteroaromatic-containing compounds bearing a central boron bridge have been prepared by short, high-yielding sequence consisting of Suzuki-coupling 8-bromoquinoline and N-Boc 2-pyrroleboronic acid, thermolytic tert-butyloxycarbonyl deprotection, subsequent chelation (either using trifluoride or triphenylborane). Both derivatives display longer wavelength a...
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