The Reactivity of Germanium Phosphanides with Chalcogens.

The reactivity of germanium phosphanido complexes with elemental chalcogens is reported. Addition of sulfur to [(BDI)GePCy] (BDI = CH{(CH)CN-2,6-iPrCH}) results in oxidation at germanium to form germanium(IV) sulfide [(BDI)Ge(S)PCy] and oxidation at both germanium and phosphorus to form germanium(IV) sulfide dicylohexylphosphinodithioate complex [(BDI)Ge(S)SP(S)Cy], whereas addition of tellurium to [(BDI)GePCy] only gives the chalcogen inserted product, [(BDI)GeTePCy]. This reactivity is different from that observed between [(BDI)GePCy] and selenium.

Lead and tin β-diketiminato amido/anilido complexes: competitive nucleophilic reactivity at the β-diketiminato γ-carbon.

The β-diketiminatolead(II)-amido and -anilido complexes, [(BDI)Pb(NRR')] (BDI = [{N(2,6-iPr2C6H3)C(Me)}2CH]; NRR' = NH(2,6-iPr2C6H3), N(iPr)2), react at the amido/anilido nitrogen atom with simple saturated electrophiles such as methyltriflate. Addition of unsaturated electrophiles to these complexes either results in the formation of a complex mixture of products, or in the case of phenylisocyanate, reaction at the γ-carbon of the β-diketiminato ligand to form a complex that is the net result of a nucleophilic attack by the γ-carbon atom of the β-diketiminato ligand at the electrophilic carbon centre of phenylisocyanate. As this reactivity contrasts with that of β-diketiminatolead(II) alkoxo complexes as well as β-diketiminatotin(II) alkoxo complexes, we examined the reactivity between phenylisocyanate and the isostructural β-diketiminatotin(II)-amido and -anilido complexes.

Why compete when you can share? Competitive reactivity of germanium and phosphorus with selenium.

Addition of one equivalent of selenium to a germanium-phosphanide complex results in insertion of selenium into the Ge-P bond, not oxidation at germanium or phosphorus. Addition of excess selenium results in oxidation at phosphorus, although of germanium oxidation is still observed.

Group 14 metal terminal phosphides: correlating structure with |J(MP)|.

A series of heavier group 14 element, terminal phosphide complexes, M(BDI)(PR(2)) (M = Ge, Sn, Pb; BDI = CH{(CH(3))CN-2,6-iPr(2)C(6)H(3)}(2); R = Ph, Cy, SiMe(3)) have been synthesized. Two different conformations (endo and exo) are observed in the solid-state; the complexes with an endo conformation have a planar coordination geometry at phosphorus (M = Ge, Sn; R = SiMe(3)) whereas the complexes possessing an exo conformation have a pyramidal geometry at phosphorus. Solution-state NMR studies reveal through-space scalar coupling between the tin and the isopropyl groups on the N-aryl moiety of the BDI ligand, with endo and exo exhibiting different J(SnC) values.

Carbon dioxide activation by "non-nucleophilic" lead alkoxides.

A series of terminal lead alkoxides have been synthesized utilizing the bulky beta-diketiminate ligand [{N(2,6-(i)Pr(2)C(6)H(3))C(Me)}(2)CH](-) (BDI). The nucleophilicities of these alkoxides have been examined, and unexpected trends were observed. For instance, (BDI)PbOR reacts with methyl iodide only under forcing conditions yet reacts readily, but reversibly, with carbon dioxide.

The synthesis of monomeric terminal lead aryloxides: dependence on reagents and conditions.

The successful synthesis of terminal lead aryloxides is shown to be dependent upon reaction conditions, including choice of solvent and alkali metal aryloxide precursor.

Effect of prolonged pressure on flowmotion: An Investigation Using an in vivo Rat Model.

The objectives of this study is to assess the effect of prolonged loading on the skin blood flowmotion in rats as measured by Laser Doppler flowmetry (LDF) using wavelets transform and power spectral in the rat skin microcirculation. External pressure of 13.3kPa (100 mmHg) was applied to the trochanter area and the distal lateral tibia of Sprague-Dawley rats via two specifically designed pneumatic indentors.