Catalysis direction selective asymmetric polymerization in chiral liquid crystal medium

Chiral allene-containing phosphines in asymmetric catalysis.

We demonstrate that allenes, chiral 1,2-dienes, appended with basic functionality can serve as ligands for transition metals. We describe an allene-containing bisphosphine that, when coordinated to Rh(I), promotes the asymmetric addition of arylboronic acids to α-keto esters with high enantioselectivity. Solution and solid-state structural analysis reveals that one olefin of the allene can coor...

Synthesis of main-chain chiral quaternary ammonium polymers for asymmetric catalysis using quaternization polymerization.

Main-chain chiral quaternary ammonium polymers were successfully synthesized by the quaternization polymerization of cinchonidine dimer with dihalides. The polymerization occurred smoothly under optimized conditions to give novel type of main-chain chiral quaternary ammonium polymers. The catalytic activity of the polymeric chiral organocatalysts was investigated on the asymmetric benzylation o...

Chiral poly-rare earth metal complexes in asymmetric catalysis

Asymmetric catalysis is a powerful component of modern synthetic organic chemistry. To further broaden the scope and utility of asymmetric catalysis, new basic concepts for the design of asymmetric catalysts are crucial. Because most chemical reactions involve bond-formation between two substrates or moieties, high enantioselectivity and catalyst activity should be realized if an asymmetric cat...

Chiral olefin ligands-new "spectators" in asymmetric catalysis.

A computer simulation study of the influence of a liquid crystal medium on polymerization.

We present a simple molecular level model based on Gay-Berne monomers linked by finitely extendable nonlinear elastic potential bonds for describing main chain polymerization in liquid crystals. We apply the model to study the influence that the order of the medium has on the characteristics of the chains obtained. We find that the chains prepared from the nematic are actually straighter than t...