SPACE INVADERS: Organometallic fragments such as the ferrocenyl group (shown in red in the picture) help to enhance cellular entry of NLS peptides. Eventually, these nontoxic conjugates find their way to the cellular nucleus as shown by fluorescence microscopy studies in this work. Intracellular delivery to biomolecular targets is still a major challenge in molecular and cell biology. We recent...

A commercial SiO2 modified by the addition of a TiO2 layer on its surface and pore walls offers support for metallocene-based ethylene polymerization catalysts with 35% improved catalytic activity. The effect such modification catalyst particle fragmentation during reactions were assessed. This was performed exposing internal cross-section several Ti/SiO2-based metallocene particles, polymerize...

Reaction of (S)-2-ferrocenyl-4-(1-methylethyl)oxazoline with [Cp*IrCl2]2 in benzonitrile with KPF6 and NaOH gave (η(5)-(S)-2-(4-(1-methylethyl))oxazolinylcyclopentadienyl)(η(5)-pentamethylcyclopentadienyl)iridium(iii) hexafluorophosphate (68%). This transformation of an iron-based into an iridium-based metallocene proceeds via the rearrangement, with loss of cyclopentadienyliron, of an intermed...

Dehydrogenation of Me(2)NH·BH(3) (1) by group 4 metallocene alkyne complexes of the type Cp(2)M(L)(η(2)-Me(3)SiC(2)SiMe(3)) [Cp = η(5)-cyclopentadienyl; M = Ti, no L (2Ti); M = Zr, L = pyridine (2Zr)] and group 4 metal amido complexes of the type M(NMe(2))(4) [M = Ti (8Ti), Zr (8Zr)] is presented.

Understanding the kinetics of olefin polymerization with Ziegler-Natta and related catalysts means identifying the main kinetic parameters such as k(p) and concentration of active sites. The high-pressure quenched-flow technique could be an absolute method for counting active sites and for activation studies of molecular catalysts. A kinetic study of metallocene catalysts and a phenoxy-imine ti...

The U(IV) linear pentacyano metallocene [U(C(5)Me(5))(2)(CN)(5)][NEt(4)](3) reacted with 2 molar equivalents of pyridine N-oxide in THF or acetonitrile to give the U(VI) complex [UO(2)(C(5)Me(5))(CN)(3)][NEt(4)](2), the first uranyl species containing the cyclopentadienyl ligand; the crystal structure revealed that the steric effects of the (C(5)Me(5)) ligand force the {UO(2)}2+ ion to deviate ...

Both metallocene and Phillips chromium catalysts are used in the commercial manufacture of polyethylene. Unlike most other systems, Chevron Chemical (CPC) platform does not use methylaluminoxane or fluoroorganic boranes. Instead, support itself serves to activate (ionize) metallocenes, which then polymerize ethylene at high activity. Most these solid acid supports can also be anchor Cr make a c...

Homogeneous surface coating of long carbon nanotubes is achieved by in situ polymerization of ethylene as catalyzed directly from the nanotube surface-treated by a highly active metallocene-based complex and allows for the break-up of the native nanotube bundles leading, upon further melt blending with HDPE, to high-performance polyolefinic nanocomposites.