New chiral pyrazine-based ligands for self-assembly reactions

Abstract

The syntheses of two families of ditopic N-heterocyclic ligands are described. All the compounds contain a central pyrazine ring connected to peripheral pyridine or bipyridine moieties, providing bipyridine-and terpyridine-like binding sites, respectively. Annellated terpene fragments render these metal chelators chiral. Thus they face the challenge of introducing stereoselectivity into the formation of chiral, multinuclear co-ordination species. † The IUPAC name for myrtenal is 6,6-dimethylbicyclo[3.3.1]hept-2en-2-carboxaldehyde. The IUPAC name for pinocarvone is pin-2(10)en-3-one.

A pair of dinuclear Re(i) enantiomers: synthesis, crystal structures, chiroptical and ferroelectric properties

“…The bis-bidentate ligands L R and L S were synthesized according to similar procedures. 10 The reaction of Re(CO) 5 Cl with L R or L S (2 : 1 molar ratio) in toluene afforded the dark-brown solid of R-1 or S-1. X-ray crystallographic analyses revealed that R-1 and S-1 are a pair of enantiomers and crystallize in the identical chiral space group P2 1 with the Flack values being 0.01(3) and 0.02(3) for R-1 and S-1, respectively, suggesting that chirality deriving from the chiral bridging ligand (L R or L S ) has been transferred successfully to the resulting solid structures.…”

Modulation of Homochiral DyIII Complexes: Single‐Molecule Magnets with Ferroelectric Properties

“…Chiral ligands L R and L S were synthesized according to similar procedures. [10] and comparison of their CD spectra verified their enantiomeric relationship (Figure 1 b). The reaction of [DyA C H T U N G T R E N N U N G (dbm) 3 H 2 O] with either L R or L S (1:1 molar ratio) in acetone/ethanol afforded pale-yellow crystals of R-1 and S-1, respectively.…”

“…Chiral ligands L R and L S were synthesized according to similar procedures 10. and comparison of their CD spectra verified their enantiomeric relationship (Figure 1 b).…”

Two mono- and dinuclear Eu(iii) enantiomeric pairs based on chiral bis-bidentate bridging ligands: synthesis, structures, luminescent and ferroelectric properties

“…The bis-bidentate ligands L R and L S were synthesized according to similar procedures. 10 Their crystal structures show a linear appearance (Fig. S2, ESI †).…”