Stereoselective synthesis of octahedral complexes with predetermined helical chirality

Abstract

Facile stereoselective synthesis of an enantiomerically pure -Ru-trisbipyridine type complex is accomplished by using a new chiral and conformationally rigid ligand, which completely predetermines the helical chirality of the metal, yielding exclusively -configuration in the present case. The ligand, abbreviated chiragen[6] is a bisbipyridine compound, where two pinene substituted bipyridine units are linked through an aliphatic Ce-chain. The two remaining coordination sites of the complex are occupied by 4,4'-dimethylbipyridine. The structure of the A-[Ru(chiragen-[6])(4,4,-dimethylbipyridine)](CF3S03)2 complex has been determined by X-ray crystallography. Metal complexes formed by chiragen ligands have potential applications in enantioselective catalysis and as chiral building blocks for polynuclear species.

Diastereoselective synthesis of coordination compounds: a chiral tripodal ligand based on bipyridine units and its ruthenium(ii) and iron(ii) complexes

“…The preparation of 1 was previously described [9,19] where the key step is a Kröhnke-type reaction. [20][21][22] The chiral pinene-type framework of 1 is deprotonated regioselectively by LDA.…”

Asymmetric Reduction of Heteroaryl Methyl Ketones Using <i>Daucus carota</i>

“…Acetyl-pyridines (2 -4) are known as aromatic components of foods, perfumes and smoking suppressants. Chiral heteroaryl alcohols have numerous applications as important intermediates in the synthesis of biological active molecules and also act as chiral ligands/auxiliaries in a number of asymmetric addition reactions [7][8][9]. There are many reports describing synthesis of chiral secondary alcohols using biocatalysts obtained from microbial/different parts of plant tissues [10][11][12].The asymmetric reductions of heteroaryl methyl ketones is a straight forward approach and a large number of chemical and biological methodologies (microbial and plant) are known to produce heterocyclic chiral alcohols of biological interest [13][14][15].…”

Diastereoselective preparation of Cu(i) and Ag(i) double helices by the use of chiral bis-bipyridine ligands

“…A new family of chiral ligands, related to the CHIRAGENS, 24 has been reported earlier. Model considerations show that one of these ligands, bis-5,6-pinene bipyridine [m-phenyl] (1) (Fig.…”