Reactions of enantiopure (S or R)-N-1-(phenyl)ethyl-2,4-X1,X2-salicylaldimine (S-H or R-H; X1, X2 = dihalogen) with Zn(II)-nitrate give bis[(S or R)-N-1-(phenyl)ethyl-2,4-X1,X2-salicylaldiminato-κ2N,O]-zinc(II), (Δ-ZnS or Λ-ZnR) with Δ/Λ-chirality induction at-metal in the C2-symmetric molecules....

The enantiopure Schiff bases ( R or S )- N -1-(X-C 6 H 4 )ethyl-2-hydroxy-1-naphthaldimine {X = H [( R or S )-HL1], p -CH 3 O [( R or S )-HL2], and p -Br [( R - or S )-HL3]} react with cobalt(II) acetate to give bis[( R or S )- N -1-(X-C 6 H 4 )ethyl-2-oxo-1-naphthaldiminato-κ 2 N , O ]-Λ/Δ-cobalt(II) {X = H [Λ/Δ-Co-( R or S )-L1], p -CH 3 O [Λ/Δ-Co-( R or S )-L2], and p -Br [Λ/Δ-Co-( R or S )-L3]} ( 1 – 3 ), respectively. Induced Λ and Δ chirality originates at the metal center of the C 2 -symmetric molecule in pseudotetrahedral geometry. Differential scanning calorimetry analyses explored the thermal stability of the complexes, which undergo reversible phase transformation from crystalline solid to isotropic liquid phase for 1 and 3 but irreversible phase transformation for 2 . Like other cobalt(II) complexes, compounds 1 – 3 exhibit a continuous ensemble of absorption and circular dichroism bands, which span from the UV to IR region and can be collected into a superspectrum. Infrared vibrational circular dichroism (IR-VCD) spectra witness the coupling between Co 2+ -centered low-lying electronic states and ligand-centered vibrations. The coupling produces enhanced and almost monosignate VCD spectra, with both effects being mode-dependent in terms of the A or B symmetry (in the C 2 point group) and distance from the Co 2+ core.

Seven enantiomeric pairs of palladium complexes, [Pd(pic)(R or S)-N-1-(phenyl)ethyl-2,4-X1,X2-salicylaldiminate)]NO3, [Pd(pic)(R or S)]NO3 (X1 = X2 = Cl, Br, I, H; X1/X2 = Br/Cl), were synthesized by reaction of enantiopure halogen‐substituted...

Condensation of 2-hydroxy-benzophenone (HL') with (R or S)-(Ar)ethylamine yields the enantiopure Schiff bases (S or R)-2-((E)-1-(1-(Ar)ethylimino)ethyl)phenol {Ar = C6H5 (S- or R-HL1), p-CH3OC6H4 (S- or R-HL2)}. These Schiff bases react...

No abstract

No abstract

No abstract

No abstract