Novel doubly bridged metallocenes have been prepared by remarkably selective two-fold alkene ring-closing metathesis. The solid state structures of 3 and 5 reveal 1,2',3,4'-connectivity and screw-shaped geometry of the molecules.

We have analyzed metal–ligand bonding in metallocenes using density functional theory (DFT) at the OPBE/TZP level. This level of theory was recently shown to be the only DFT method able to correctly predict the spin ground state of iron complexes, and similar accuracy for spin ground states is found here. We considered metallocenes along the first-row transition metals (Sc–Zn) extended with alk...

Aromaticity in novel cyclic all-pnictogen heterocyclic anions, P2N3(-) and P3N2(-), and in their heavier analogues is studied using quantum mechanical computations. All geometrical parameters from optimized geometry, bonding, electron density analysis from quantum theory of atoms in molecules, nucleus-independent chemical shift, and ring current density plots support their aromaticity. The arom...

The electronic structure of tne closed shell metallocenes bis(7r-cyclopentadienyl)magnesium (1), bisbenzene chromium (2), ferrocene (3) and cyclopentadienyl benzene manganese (4) has been studied in the ground state as well as in the low-lying cationic states. The computational framework is a semiempirical INDO Hamiltonian, the theoretical framework for the investigation of the cationic hole-st...

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...

Organometallic complexes offer potential for design as anticancer drugs. They can act as inert scaffolds and specifically inhibit enzymes such as kinases, or as pro-drugs which undergo activation by various mechanisms. The activation of metallocenes, arene, alkyl or aryl complexes by hydrolysis, and metalor ligandbased redox reactions is discussed.