81660-73-3Relevant articles and documents
Very Facile Polarity Umpolung and Noncovalent Functionalization of Inorganic Nanoparticles: A Tool Kit for Supramolecular Materials Chemistry
Zeininger, Lukas,Petzi, Stefanie,Sch?namsgruber, J?rg,Portilla, Luis,Halik, Marcus,Hirsch, Andreas
, p. 14030 - 14035 (2015)
The facile assembly of shell-by-shell (SbS)-coated nanoparticles [TiO2-PAC16]@shell1-7 (PAC16=hexadecylphosphonic acid), which are soluble in water and can be isolated as stable solids, is reported. In these functional architectures, an umpolung of dispersibility (organic apolar versus water) was accomplished by the noncovalent binding of ligands 1-7 to titania nanoparticles [TiO2-PAC16] containing a first covalent coating with PAC16. Ligands 1-7 are amphiphilic and form the outer second shell of [TiO2-PAC16]@shell1-7. The tailor-designed dendritic building blocks 3-5 contain negative and positive charges in the same molecule, and ligands 6 and 7 contain a perylenetetracarboxylic acid dimide (PDI) core (6/7) as a photoactive reporter component. In the redox and photoactive system [TiO2-PAC16]@shell7, electronic communication between the inorganic core to the PDI ligands was observed. Nanochameleons with switchable dispersion behavior: In these new shell-by-shell architectures, ionic and redox-active amphiphiles make the difference because they form an outer ligand shell that provides polarity umpolung, water solubility, and facile nanoparticle functionalization (see figure).
A mesoporous organosilica grafted Pd catalyst (MOG-Pd) for efficient base free and phosphine free synthesis of tertiary butyl esters via tertiary-butoxycarbonylation of boronic acid derivatives without using carbon monoxide
Ghosh, Kajari,Molla, Rostam Ali,Iqubal, Md. Asif,Islam
, p. 3540 - 3551 (2015/06/25)
A mesoporous organosilica grafted palladium(ii) catalyst was synthesized and characterized using various spectroscopic techniques. Its catalytic activity was evaluated for the synthesis of tertiary butyl esters via tert-butoxycarbonylation of boronic acid
Transition-metal catalyzed oxidations. 7. Zirconium-catalyzed oxidation of primary and secondary alcohols with hydroperoxides
Krohn, Karsten,Vinke, Ingeborg,Adam, Horst
, p. 1467 - 1472 (2007/10/03)
A new procedure for the oxidation (dehydrogenation) of primary and secondary alcohols employing Zr(O-t-Bu)4 or Zr(O-n-Pr)4/tert-butyl hydroperoxide/3 A molecular sieves is presented. Secondary alcohols - if not severely sterically hindered - are usually converted quantitatively to the corresponding ketones. Esters or acids can be by products in the reaction of primary alcohols. However, the aldehydes are obtained in good yield by lowering the reaction temperature, decreasing the amount of TBHP or replacing TBHP by cumene hydroperoxide (CHP), and/or exchanging the catalyst Zr(O-t-Bu)4 by Zr(O-n-Pr)4 or silica gel-supported Zr(OR)(x). A remarkable selectivity of equatorial alcohol groups (e.g., 11 and 13) is observed in contrast to chromium(VI)-based oxidations. Strongly chelating substrates such as furfuryl alcohol (18) or 1,2-diol 25 that prevent hydride transfer in the six-membered transition state A are not converted.
