Palladium nanoparticle-cored G1-dendrimer stabilized by carbon–Pd bonds: synthesis, characterization and use as chemoselective, room temperature hydrogenation catalyst
作者:Venugopal K. Ratheesh Kumar、Karical R. Gopidas
DOI:10.1016/j.tetlet.2011.04.011
日期:2011.6
Palladium nanoparticle-cored Fréchet type G1-dendrimer (Pd-G1) stabilized by Pd–carbon bonds is synthesized and characterized by IR, NMR, UV–Vis and TEM. Pd-G1 was found to be a highly efficient, chemoselective and reusable catalyst for the room temperature hydrogenation of carbon–carbon multiple bonds. Reducible functionalities like CHO, CO, COOR, CN, NO2 and halogens were unaffected. Pd-G1 is projected
One-pot formation of aza-enolates from secondary amines and condensation to esters and alkyl bromides
作者:Alice Chevalley、Jean-Pierre Férézou
DOI:10.1016/j.tet.2012.04.105
日期:2012.7
Starting from commercial secondary amines, a one-pot procedure allows a direct access to enaminones through a one-pot deprotonation/oxidation/in situ re-deprotonation/acylation sequence without intermediate isolation of the intermediate Schiff base or its corresponding enamine tautomer. An alternative one-pot sequence involving a similar oxidation step followed by one or two alkylation steps yields
(EN) The present invention provides compounds of formula (I) in which R is as defined in the specification, or a pharmaceutically acceptable metabolically labile ester or amide thereof, or a pharmaceutically acceptable salt thereof, which are useful as antagonists of one or more of the actions of L-glutamate at metabotropic excitatory amino acid receptors.(FR) Cette invention concerne des composés de formule (I), dans laquelle R est tel que défini dans le descriptif, ou un ester ou amide pharmaceutiquement acceptable de ces composés qui est métaboliquement labile, ou encore un sel pharmaceutiquement acceptable de ces composés, qu'on utilise comme antagonistes d'une ou de plusieurs actions du L-glutamate au niveau des récepteurs d'acides aminés excitateurs métabotropiques.
Isomerization of an unsymmetrical ketoxime ether is effected using at least one Lewis acid selected from titanium chloride, titanium bromide, aluminium chloride, aluminium bromide, boron chloride, and boron bromide as isomerizing agents. Examples of the Lewis acid are titanium tetrachloride, titanium trichloride, aluminium trichloride, aluminium tribromide, boron trichloride, and boron tribromide. The ketoxime ether is preferably an anti-isomer or a syn-isomer of a compound represented by the formula (I) or a mixture of the anti-isomer and the syn-isomer:
wherein R¹ represents an aryl group, an aralkyl group or an alkyl group and R² and R³ each represents an aralkyl group or an alkyl group, with a proviso that R¹ and R² are not identical.