Organoiron Complexes, Olefin Isomerization, 1,2-Dimethoxyethylene Displacement of 2-methvlpropene from [Fp(Me2C = CH2)]BF4 (Fp = (/?5-C5H5)Fe(CO)2) by Z-1,2-dimethoxyethylene (Z-DME) gives [Fp(Z-DME)]BF4. Displacement by E-1,2dimethoxyethylene (E-DME), in contrast, does not give the expected complex of E-DME, but rather the complex of the Z-alkene. A mechanism involving scission of the C = C bo...

Dinuclear nickelphenoxyiminato olefin polymerization catalysts based on rigid p-terphenyl frameworks are reported. Permethylation of the central arene of the terphenyl unit and oxygen substitution of the peripheral rings ortho to the aryl-aryl linkages blocks rotation around these linkages allowing atropisomers of the ligand to be isolated. The corresponding syn and anti dinickel complexes (25-...

1-Phosphanorbornadiene derivatives were grafted onto various periodically organized mesoporous powders, including a new zirconia/silica mixed oxide synthesized by aerosol techniques. After complexation with the [Rh(CO)2]+ fragment, these materials were revealed to be more active in olefin hydrogenation than their homogeneous counterparts. The reasons for this higher activity are discussed in th...

The conversion of cis-2-butene with deuterium over a well-defined Pd/Fe(3)O(4) model catalyst was studied by isothermal pulsed molecular beam (MB) experiments under ultra high vacuum conditions. This study focuses on the processes related to dissociative hydrogen adsorption and diffusion into the subsurface of Pd nanoparticles and their influence on the activity and selectivity toward competing...

Two novel andrographolide analogues with the structural motif of Δ(8,17)-alkene exo-to-endo isomerization, AI78 and AI89, were semi-synthesized firstly. Two series of derivatives were designed and synthesized based on the synthetic pathway (including series I: olefin isomerizing to endocyclic Δ(8,9) and series II: olefin isomerizing to endocyclic Δ(7,8)). The anti-influenza virus activity in vi...

A novel chelate-controlled intermolecular oxidative Heck reaction is reported that proceeds with a wide range of nonresonance stabilized alpha-olefin substrates and organoboron reagents to afford internal olefin products in good yields and outstanding regio- and E: Z stereoselectivities. Pd-H isomerization, common in many Heck reactions, is not observed under these mild, oxidative conditions. T...

The mechanisms of the gas-phase elimination kinetics of 1-chloro-3-methylbut-2-ene and 3-chloro-3-methylbut-1ene and their interconversion have been examined at MP2 and DFT levels of theory. These halide substrates yield isoprene and hydrogen chloride. The results MPW1PW91 calculations agree with the experimental kinetic parameters showing the elimination reaction occurs at greater rate for 1-c...

We report on the catalytic activity of commercially available Ru-indenylidene and "boomerang" complexes C1, C2 and C3 in acyclic diene metathesis (ADMET) polymerization of a fully renewable α,ω-diene. A high activity of these catalysts was observed for the synthesis of the desired renewable polyesters with molecular weights of up to 17000 Da, which is considerably higher than molecular weights ...