Tris(hydroxypropyl)phosphine Oxide: A Chiral Three-Dimensional Material with Nonlinear Optical Properties

The achiral C_(3v) organic phosphine tris(hydroxypropyl)phosphine oxide (1) crystallizes in the unusual chiral hexagonal space group P6_3. The structure is highly ordered because each phosphine oxide moiety forms three hydrogen bonds with adjacent hydroxy groups from three different molecules. The properties of the crystals and the presence of hydrogen bonding interactions were investigated using single crystal Raman spectroscopy. The crystals show nonlinear optical properties and are capable of efficient second harmonic generation

Anodic deposition of a robust iridium-based water-oxidation catalyst from organometallic precursors

Artificial photosynthesis, modeled on natural light-driven oxidation of water in Photosystem II, holds promise as a sustainable source of reducing equivalents for producing fuels. Few robust water-oxidation catalysts capable of mediating this difficult four-electron, four-proton reaction have yet been described. We report a new method for generating an amorphous electrodeposited material, principally consisting of iridium and oxygen, which is a robust and long-lived catalyst for water oxidation, when driven electrochemically. The catalyst material is generated by a simple anodic deposition from Cp*Ir aqua or hydroxo complexes in aqueous solution. This work suggests that organometallic precursors may be useful in electrodeposition of inorganic heterogeneous catalysts

Tethered pyrazolyl phosphinate: pyrazolyl-N- and phosphoryl-O-metal coordination in Ph<SUB>2</SUB>P(O){OCH<SUB>2</SUB>CH<SUB>2</SUB>(3,5-Me<SUB>2</SUB>Pz)}

Phosphorus pyrazolides, P(O)(3,5-Me2Pz)3 or RP(E)(3,5-Me2Pz)2 [E = S or O, R = Me or Ph], are hydrolytically sensitive particularly upon interaction with transition metal ions. In this paper, we report a new tethered pyrazolyl phosphinate, Ph2P(O){OCH2CH2(3,5-Me2Pz)} DPEP (1), where the pyrazolyl group is separated from the phosphorus by means of an ethyleneoxy spacer. 1 has two potential coordination sites in the form of a phosphoryl oxygen atom and a pyrazolyl nitrogen atom. 1 forms hydrolytically stable complexes, (DPEP&#183;CoCl2)n (2), (DPEP)2&#183;CuCl2 (3), (DPEP&#183;ZnCl2)n (4), and (DPEP)2&#183;PdCl2 (5). The cobalt(II) and the zinc(II) complexes 2 and 4 show a zigzag polymeric structure in the solid state with a tetrahedral coordination geometry around the metal ion; the ligand DPEP coordinates through its phosphoryl oxygen and the pyrazolyl nitrogen to two neighboring metal ions and functions as a bridging ligand to form the polymeric structure. In contrast to 2 and 4, the copper(II) and the palladium(II) complexes 3 and 5 show a square-planar geometry around the metal ion. Exclusive coordination through the pyrazolyl nitrogens of the ligand 1 is observed. An extensive supramolecular sheetlike two-dimensional polymeric network is observed in the solid-state structures of 3 and 5 as a result of two weak interactions: (a) an intermolecular C-H---O interaction involving the phosphoryl oxygen and an aromatic C-H and (b) a p-p face-to-face stacking interaction between the phenyl groups of two adjacent molecules