Silane ligand

Fig. 4 Schematic illustration of synthesis of multifunctional nanoparticles starting from a w/o microemulsion, b solubilization of fluorescent dye in the microemulsion core, c formation of silica nanoparticle and encapsulation of fluorescent dye, d condensation of silane ligand and chelation of Gd(lll), e post coating with silica, and f extraction of nanoparticles...

Synthesis of Platinum and Rhenium Complexes with a Chelating (Phenylthiomethyl)silane Ligand... 

Hexachloroplatinic acid in isopropanol (Speier s catalyst) is the most commonly used hydrosilylation catalyst because of its broad applicability and effectiveness at very low concentrations. A generally accepted mechanism for homogeneous platinum catalysed hydrosilylation involves reduction of Pt(IV) to Pt(II) by the silane, ligand substitution by the alkene, oxidative addition of SiH to the metal, rearrangement to a a-bonded complex and finally reductive elimination of the product and recycle of the catalyst 206 208. The basic mechanism is summarised in Scheme 2. 

Substitution of two cis H2 ligands conveniently produces the first structurally characterized chelating bis(silane) systems, RuH2[(SiHMe2)2X](PCy3)2 [Eq. (11.7)].27 The bis(silane) ligand is relatively strongly bound here [dSiH = 1.73-1.84 A... 

In RuH2(H2)(SiHPh3)(PCy3)2, which contains both H2 and silane ligands, the ( /2-H2)(> 2-HSiR3) isomer (8) is only about 2 kcal/mol more stable experimentally and calculationally (as a PH3 model complex with R = H) than the ( 72-H2)2(H)(SiR3) isomer (9).58 However, differences in phosphine orientation and... 

Dynamics of Silane Ligands and Exchange with cis Hydrides... 

Thus far, selectivity differences for heterogeneous surfaces as opposed to homogeneous surfaces have been addressed under the assumption that each adsorj on site interacts independently of its microenvironment. Nonadditivity has previously been shown to occur with respect to endcapped reverse-phase HPLC stationary phases, possessing two silane ligands (106,107). In taking into account the microenvironment associated with each separate solute/adsorption site interaction, Eq. (15) can be further modifie as... 

Waals fadtus of the silane ligand or by dosest-ht dis rams described by Berendson (lOS) but permits the preparation of silica based anion ex> clipngeia wiA sey limes th lunptioiial groups that are currently available op bonded silicgrbased supports. 

Acid Hydrolysis of Bonded Phases. One of the problems encountered with acid hydrolysis of silane-bonded phases Is that dimerization of the silane ligands Is favored (42), as Illustrated In Reaction 1 of Figure 1 and Table I. Such dimerization can be helpful for the... 

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