New reactivity patterns of copper(I) and other transition metal NHC complexes: application to ATRC and related reactions

Synthesis, Properties, and Two-Dimensional Adsorption Characteristics of [6]Hexahelicene-7-carboxylic acid

A convergent synthesis of racemic [6]hexahelicene-7-carboxylic acid by cross-coupling of a bicyclic and a tricyclic component is described. A metal-catalyzed ring-closure is also a fundamental component of the synthetic approach. Scanning tunneling microscopy (STM) measurements of the racemate self-assembled on Au(111) at liquid-solid interface revealed the formation of ordered racemic 2D crystals.

Crystal structure of catena-poly[hemi[1,3-bis-(2,6-diisoprop-ylphenyl)imidazolium] [[μ3-acetato-κ(3) O:O:O'-tri-μ2-acetato-κ(6) O:O'-dicopper(II)(Cu-Cu)]-μ-chlorido] di-chloro-methane sesqui-solvate]

The title copper(II) complex, {(C27H37N2)[Cu4(CH3COO)8Cl]·3CH2Cl2} n , is a one-dimensional coordination polymer. The asymmetric unit is composed of a copper(II) tetra-acetate paddle-wheel complex, a Cl(-) anion situated on a twofold rotation axis, half a 1,3-bis-(2,6-diisoprop-ylphenyl)imidazolium cation (the whole mol-ecule being generated by twofold rotation symmetry) and one and a half of a di-chloro-methane solvent mol-ecule (one being located about a twofold rotation axis). The central metal-organic framework comprises of a tetra-nuclear copper(II) acetate 'paddle-wheel' complex which arises from the dimerization of the copper(II) tetra-acetate core comprising of three μ2-bidentate acetate and one μ3-tridentate acetate ligands per binuclear paddle-wheel complex. Both Cu(II) atoms of the binuclear component adopt a distorted square-pyramidal coordination geometry (τ = 0.04), with a Cu⋯Cu separation of 2.6016 (2) Å. The apical coordination site of one Cu(II) atom is occupied by an O atom of a neighbouring acetate bridge [Cu-O = 2.200 (2) Å], while that of the second Cu(II) atom is occupied by a bridging chloride ligand [Cu⋯Cl = 2.4364 (4) Å]. The chloride bridge is slightly bent with respect to the Cu⋯Cu inter-nuclear axis [Cu-Cl-Cu = 167.06 (6)°] and the tetra-nuclear units are located about a twofold rotation axis, forming the one-dimensional polymer that propagates along [101]. Charge neutrality is maintained by the inclusion of the 1,3-bis-(2,6-diisoprop-ylphenyl)imidazolium cation within the crystal lattice. In the crystal, the cation and di-chloro-methane solvent mol-ecules are linked to the coordin-ation polymer by various C-H⋯O and C-H⋯Cl hydrogen bonds. There are no other significant inter-molecular inter-actions present.

Non-linear, cata-Condensed, Polycyclic Aromatic Hydrocarbon Materials: A Generic Approach and Physical Properties

A generic approach to the regiospecific synthesis of halogenated polycyclic aromatics is made possible by the one- or two-directional benzannulation reactions of readily available (ortho-allylaryl)trichloroacetates (the “BHQ” reaction). Palladium-catalysed cross-coupling reactions of the so-formed haloaromatics enable the synthesis of functionalised polycyclic aromatic hydrocarbons (PAHs) with surgical precision. Overall, this new methodology enables the facile mining of chemical space in search of new electronic functional materials.

An Approach to the Synthesis of Functionalized Polycyclic Aromatic Hydrocarbons

The application of a new benzannulation reaction for the regiocontrolled synthesis of functionalized chrysenes is reported. The initial benzannulation and the subsequent halogen displacement reactions are both highly regiospecific, which thereby enables the regiocontrolled synthesis of a variety of 4,10-disubstituted chrysenes from commercially available 1,5-dihydroxynaphthalene.

Radicals in transition metal catalyzed reactions? transition metal catalyzed radical reactions?: a fruitful interplay anyway: part 3: catalysis by group 10 and 11 elements and bimetallic catalysis

This review summarizes the current status of transition metal catalyzed reactions involving radical intermediates in organic chemistry. This part focuses on radical-based methods catalyzed by group 10 and group 11 metal complexes. Reductive and redox-neutral C-C bond formations catalyzed by low-valent metal complexes as well as catalytic oxidative methods are reviewed. Catalytic processes which rely on the combination of two metal complexes are also covered.