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AG Orpen

Publications and source records attributed to AG Orpen.

6 recordsLinked to original sources
PubMed1999

Double Insertion of Coordinated Phosphanylalkyne Ligands into a Pt-C(6)F(5) Bond.

Enhanced reactivity is shown by uncoordinated C identical withC bonds in the proximity of a metal in phosphanylacetylene complexes. cis-[Pt(C(6)F(5))(2)(thf)(2)] reacts with [M(C(6)F(5))(2)(PPh(2)C identical withCPh)(2)] (M=Pt, Pd) to form binuclear complexes containing the novel 2,3-bis(diphenylphosphanyl)-1,3-butadien-1-yl bridging ligand. Substitution of the solvent ligands with, for example, PPh(2)H (see picture) provides species that could be characterized by X-ray crystallography.

Journal Article↗
PubMed1999

Conformational behaviour of bridging diphenylphosphido ligands.

Data retrieved from the Cambridge Structural Database for crystal structures containing (µ-diphenylphosphido) metal complexes, [M(2){µ-PPh(2)}] (where M is a d-block element), have been analysed to evaluate the conformational behaviour of these species. The observed distribution of torsion angles about the P-C bonds has been compared with the potential energy surface (PES) for phenyl rotations in a representative species [(AuBr)(2){µ-PPh(2)}](-) computed using the universal force field. Good agreement was obtained between the low-energy (<8 kJ mol(-1) above the global minimum) regions of the PES and the occupied regions of the two-dimensional P-Ph rotor conformation space. Phenyl ring rotations occur by coupled, geared disrotatory and uncoupled conrotatory motions of the phenyl groups in this and other classes of PPh(2) rotors.

Journal Article↗
PubMed1999

A chemically functionalizable nanoporous material

Although zeolites and related materials combine nanoporosity with high thermal stability, they are difficult to modify or derivatize in a systematic way. A highly porous metal coordination polymer [Cu3(TMA)2(H2O)3]n (where TMA is benzene-1,3,5-tricarboxylate) was formed in 80 percent yield. It has interconnected [Cu2(O2CR)4] units (where R is an aromatic ring), which create a three-dimensional system of channels with a pore size of 1 nanometer and an accessible porosity of about 40 percent in the solid. Unlike zeolites, the channel linings can be chemically functionalized; for example, the aqua ligands can be replaced by pyridines. Thermal gravimetric analysis and high-temperature single-crystal diffractometry indicate that the framework is stable up to 240 degreesC.

Journal Article↗