Comparison of the X-ray crystal structures of four closely related Mo(CO)5(R2PXR′) (R2 = OCH2CMe2CH2O, XR′ = S-2-Pr, NHC6H4-4-Me; R2 = Ph2, XR′ = NHC6H4-2-Me, OC6H4-4-SMe) complexes

The X-ray crystal structures of four closely related Mo(CO)₅(R₂PXR) (R₂ = OCH₂CMe₂CH₂O, XR = S-2-Pr, NHC₆H₄-4-Me; R₂ = Ph₂, XR = NHC₆H₄-2-Me, OC₆H₄-4-SMe) complexes have been determined. The R₂PXR ligands are oriented so that the P—X bond and one of the Mo—C bonds are nearly eclipsed. This results in the distortion of the octahedral coordination geometry via tilting of the Mo(CO)₅ group away from the XR group. As observed in related complexes, the Mo—C bond of the carbonyl trans to the phosphorus-donor group is shorter than are the Mo—C bonds of the carbonyls trans to carbonyls. In contrast, no significant differences were observed between the Mo—C bonds of carbonyls trans to phosphites and the Mo—C bonds of carbonyls trans to phosphinites. The conformations of the 1,3,2-dioxaphosphorinanes were distorted chairs with the P end of the chair significantly flattened relative to the seat of the chair. This conformation is similar to that which has been observed for 1,3,2-dioxaphosphorinanes in other transition metal complexes.     

Double Z-pinch hohlraum drive with excellent temperature balance for symmetric inertial confinement fusion capsule implosions

A double Z pinch driving a cylindrical secondary hohlraum from each end has been developed which can indirectly drive intertial confinement fusion capsule implosions with time-averaged radiation fields uniform to 2%-4%. 2D time-dependent view factor and 2D radiation hydrodynamic simulations using the measured primary hohlraum temperatures show that capsule convergence ratios of at least 10 with average distortions from sphericity of /r200 MJ.     

Ligand exchange reactions within the coordination sphere of a molybdenum eta 2(4e)-alkyne complex: the formation of an indole in a cascade reaction involving an alkyne and isonitrile ligands

The exchange of phosphorus-containing ligands within the coordination sphere of molybdenum alkyne complexes is shown to be facile, a similar reaction with CNxyl (xyl = C6H3Me(2)-2,5) results in a remarkable coupling between the alkyne and three isonitrile ligands and C-H bond activation.     

Dynamics of inter- and intrastrand hole transport in DNA hairpins

The dynamics of photoinduced electron transfer has been investigated in DNA hairpins possessing a stilbenedicarboxamide (Sa) electron acceptor, a guanine (G) primary donor, and two adjacent guanines (GG) as secondary donors. Hole transport from G to GG across a single A is more rapid than across AA or T by factors of 20 +/- 7 and 40 +/- 15, respectively. Intrastrand hole transport across a single A is more rapid than interstrand transport by a factor of 7 +/- 3.     

The formation of ReS(2) inorganic fullerene-like structures containing Re(4) parallelogram units and metal-metal bonds

The encapsulation of ReO(x) within ReS(2) inorganic fullerene-like cages is described for the first time. The encapsulate was prepared by the sulfidization of both hand-milled and ball-milled samples of ReO(2); partial conversion of the oxide to the sulfide was achieved with the degree of sulfidization depending on the exposure to the sulfidizing agent, H(2)S.     

Electrochemistry of chalcogen compounds: prediction of antioxidant activity

Synthesis and characterisation of organochalcogens has demonstrated a high correlation between their electrochemical oxidation potential on the glassy carbon electrode, their activity in bioassays and an unprecedented antioxidant activity in neuronal cell culture (EC50 approximately 20 nM) making electrochemical methodology a valuable tool in drug design for Alzheimer's and related diseases.     

Twelvefold Functionalization of an Icosahedral Surface by Total Esterification of [B12(OH)12]2-: 12(12)-Closomers

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