Abstract

C2 Symmetric acyclic ligands 1a-1e, macrocyclic ligands 2a-2d and 3, and their copper(I) and silver(I) complexes were studied by UV, NMR and CD spectroscopy. The stability constants of the metal-1a and -1b complexes with 1:1 and 1:2 stoichiometries in acetonitrile were determined by spectrometric titrations. Evidence of tetrahedral coordination for complex [Ag(1a)2]+ was obtained from the complexation induced shifts (CIS) and NOE effects, and corroborated by molecular modelling. Ligands with phenyl rings on the stereogenic centers (1a, c and 2) exhibit strong Cotton effect (CE) in the region of 1Bb band, which is absent in the ligands with benzyl groups on the stereogenic center (1b, 3). This effect is ascribed to the exciton coupling (EC) of two aromatic chromophores on the stereogenic center. For the ligands 1a and 2a EC changes the sign on complexation to Cu+, revealing opposite helicity of the free and complexed ligand.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.