Controlled hydrolysis of AlMe to tetramethylalumoxane and a new look at incipient adducts with water.

We present an efficient route to tetramethylalumoxane by the controlled hydrolysis of AlMe in the presence of pyridine. The AlMe(pyr) hydrolysis by 0.5 and 1 equiv.

MP2-Based Correction Scheme to Approach the Limit of a Complete Pair Natural Orbitals Space in DLPNO-CCSD(T) Calculations.

The domain-based local pair natural orbital (PNO) coupled-cluster DLPNO-CCSD(T) method has been proven to provide accurate single-point energies at a fraction of the cost of canonical CCSD(T) calculations. However, the desired "chemical accuracy" can only be obtained with a large PNO space and extended basis set. We present a simple yet accurate and efficient correction scheme based on a perturbative approach.

Crystal structure of bis-[()-2-(2-hy-droxy-benzyl-amino)-4-methyl-penta-noato-κ , ](1,10-phenanthroline-κ ,')cadmium dihydrate.

The asymmetric unit of the mononuclear mixed-ligand title complex, [Cd(CHNO)(CHN)]·2HO, contains two crystallographically independent mol-ecules that differ insignificantly in their geometrical parameters. In both, the Cd cation lies on a twofold rotation axis and is coordinated in a distorted octa-hedral fashion to two monodeprotonated residues of the l-leucine-derived ligand ()-2-(2-hy-droxy-benzyl-amino)-4-methyl-penta-noic acid (), as well as to a 1,10-phenanthroline ligand in a κ ,' mode. The former coordinate in an ,-chelating mode, exhibiting a -,' mutual disposition.

Structural characterization and DFT study of bis-{()-2-[(2-hy-droxy-benz-yl)amino]-3-(4-hy-droxy-phen-yl)propano-ato-κ,}(1,10-phenanthroline-κ,')cadmium(II) tetra-hydrate.

In the title compound, [Cd(CHO)(CHN)]·4HO, the Cd ion lies on a twofold rotation axis and is chelated by two monodeprotonated residues of the l-tyrosine-derived ligand ()-2-[(2-hy-droxy-benz-yl)amino]-3-(4-hy-droxy-phen-yl)propanoic acid () in a κ, amino acid chelating mode, exhibiting an (,')- disposition, and by 1,10-phenanthroline in a κ,' mode. The latter ligand is also located about the twofold rotation axis that bisects the central six-members ring. The phenolic groups remain protonated and non-coordinating and take part as acceptors in the intra-molecular hydrogen bonds with the amino groups of the acido ligands.