Issue 4, 2003

Complexation of alkali metal and alkaline earth ions by anthracene based fluorophores with one and two appended monoaza coronand receptors

Abstract

The complexation of alkali metal ions by 13-[2-(10-ethyl-9-anthryl)ethyl]-1,4,7,10-tetraoxa-13-azacyclopentadecane, 1, and 13-(2-{10-[2-(1,4,7,10-tetraoxa-13-azacyclopentadecanyl)ethyl]-9-anthryl}ethyl)-1,4,7,10-tetraoxa-13-azacyclopentadecane, 2, to form fluorescent complexes in acetonitrile is reported. The fluorescence quantum yields, ϕ, are 0.25 and 0.03 for 1 and 2, respectively. At 298.2 K and I = 0.05 mol dm−3 (NEt4ClO4) the [M1]+ complexes are characterised by complexation constants K1 = (1.28 ± 0.01) × 105 (ϕ1 = 0.71), (9.27 ± 0.04) × 104 (ϕ1 = 0.64), (1.73 ± 0.02) × 104 (ϕ1 = 0.60), (3.08 ± 0.05) × 103 (ϕ1 = 0.53) and (2.17 ± 0.04) × 103 (ϕ1 = 0.34) dm3 mol−1, respectively, as M+ changes from Li+ to Cs+. Fluorophore 2 forms weakly fluorescent [M2]+ and possibly the “sandwich” complex, [M2]+, which are jointly characterised by complexation constants K1= (7.1 ± 0.03) × 105, (5.2 ± 0.3) × 105, (1.00 ± 0.03) × 104 and (1.8 ± 0.2) × 104 dm3 mol−1 for Li+, Na+, K+ and Rb+ and [M22]2+ characterised by K2 = (6.41 ± 0.01) × 104 (ϕ2 = 0.73), (4.84 ± 0.01) × 104 (ϕ2 = 0.53), (1.59 ± 0.06) × 103 (ϕ2 = 0.39) and (6.8 ± 0.1) × 102 dm3 mol−1 (ϕ2 = 0.15). (Cs+ induced insufficient fluorescence in 2 for quantitative study.) The alkaline earths form more stable complexes with 1 and 2 characterised by K1 and K2 ≥ 107 dm3 mol−1. The factors governing fluorescence and complex stability are discussed and the syntheses of 1 and 2 are described.

Graphical abstract: Complexation of alkali metal and alkaline earth ions by anthracene based fluorophores with one and two appended monoaza coronand receptors

Supplementary files

Article information

Article type
Paper
Submitted
21 Oct 2002
Accepted
23 Dec 2002
First published
28 Jan 2003

Dalton Trans., 2003, 521-526

Complexation of alkali metal and alkaline earth ions by anthracene based fluorophores with one and two appended monoaza coronand receptors

J. P. Geue, N. J. Head, A. D. Ward and S. F. Lincoln, Dalton Trans., 2003, 521 DOI: 10.1039/B210269B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements