Double-armed and tetra-armed cyclen-based cryptands. Issue 5 (4th May 2017)

• Record Type: Journal Article
• Authors: Ikeda, Mari; Sah, Ajay Kumar; Iwase, Miki; Murashige, Rina; Kuwahara, Shunsuke; Habata, Yoichi
• Is Part Of: Supramolecular chemistry. Volume 29:Issue 5(2017)
• Page Start: 370
• Page End: 377
• Publication Date: 2017-05-04
• Subjects: Cyclene -- cryptand -- Ag+−π interaction -- argentivorous molecule; Macromolecules -- Periodicals; Supramolecular chemistry -- Periodicals; 547.005
• DOI: 10.1080/10610278.2016.1239829
• Languages: English
• ISSNs: 1061-0278

Abstract

Abstract: Double-armed and tetra-armed cyclen-based cryptands (1a –1d and2 ) that bridge two aromatic rings by diethyleneoxy and triethyleneoxy units were prepared. The CSI-MS of 1:1 mixtures ([Ag + ]/[ligand]) indicated that these new cryptands form 1:1 complexes with Ag + . The log K values for the interaction between Ag + and2 was greater than those of1a –1d, double-armed cyclens (3a –3c and4 ), and tetra-armed cyclen (5 ). The Ag + -ion-induced 1 H NMR spectral changes suggest that the Ag + – π interactions of the Ag + complexes with the cryptands (1a –1d and2 ) are stronger than those in Ag + /double-armed and tetra-armed cyclens. To visualise the Ag + − π interactions, the isosurfaces of the LUMO and HOMOs of the Ag + complexes were calculated at the B3LYP/3–21G(*) theoretical level. The LUMO of the Ag + ion is distorted by interaction with the HOMOs of the aromatic side arms. The calculations reveal Ag + − π interactions between the Ag + ion and the aromatic side arms, and these are shown graphically. Abstract :