𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Metal Complexes with Macrocyclic Ligands, IV. Synthesis, Properties and Kinetics of Complexation with Three N-methyl Substituted 1,4,8,11-tetraazacyclotetradecanes

✍ Scribed by Rudolf Buxtorf; Thomas A. Kaden

Publisher
John Wiley and Sons
Year
1974
Tongue
German
Weight
467 KB
Volume
57
Category
Article
ISSN
0018-019X

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

The synthesis, properties and complexation of 1‐methyl‐1,4,8,11‐tetraazacyclotetradecane (1‐MeCyclam‐14), 1,5‐dimethyl‐1,5,8,12‐tetraazacyclotetradecane (2‐MeCyclam‐14) and 1,4,8,11‐tetramethyl‐1,4,8,11‐tetraazacyclotetradecane (4‐MeCyclam‐14) are described.

While the Ni^2+^ and Cu^2+^ complexes of 1‐MeCyclam‐14 and 2‐MeCyclam‐14 exhibit square planar geometries, 4‐MeCyclam‐14 forms Ni^2+^ and Cu^2+^ complexes, whose absorption spectra are best explained by assuming pentaco‐ordination of the metal ions.

The complexation rate of the three N‐methyl substituted macrocycles with Cu^2+^ and Ni^2+^ is slower than can be accounted for by water exchange and little affected by introducing methyl groups at the nitrogens. Both results are in contrast to what is known for open chain amine ligands. A mechanism for the complexation is proposed, which also explains why the products of the reaction of 4‐MeCyclam‐14 with Cu^2+^ and Ni^2+^ are pentaco‐ordinated.

📜 SIMILAR VOLUMES

Metal Complexes with Macrocyclic Ligands
Metal Complexes with Macrocyclic Ligands, V. Formation and dissociation kinetics of the pentaco-ordinated Ni2+, Cu2+, Co2+ and Zn2+ complexes with 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane
✍ Liselotte Hertli; Thomas A. Kaden 📂 Article 📅 1974 🏛 John Wiley and Sons 🌐 German ⚖ 308 KB

## Abstract The formation and dissociation kinetics of the pentaco‐ordinated Cu^2+^, Ni^2+^, Co^2+^ and Zn^2+^ complexes with 1,4,8,11‐tetramethyl‐1,4,8,11‐tetraazacyclotetradecane (4‐MeCyclam‐14) was studied by pH‐stat techniques and spectrophotometrically. The rates of the reactions between 4‐MeC

Metal complexes with macrocyclic ligands
Metal complexes with macrocyclic ligands. XVI. Spectrophotometric and thermodynamic studies of solvents and unidentate ligands interaction with the pentacoordinate Co2+-, Ni2+- and Cu2+-complexes of 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane
✍ Mauro Micheloni; Piero Paoletti; Stephan Bürki; Thomas A. Kaden 📂 Article 📅 1982 🏛 John Wiley and Sons 🌐 German ⚖ 479 KB

## Abstract The interaction of solvents and of unidentate ligands such as N, SCN^−^, OCN^−^ and OH^−^ with the Co^2+^‐, Ni^2+^ and Cu^2+^‐complexes of 1,4,8,11‐tetramethyl‐1,4,8,11‐tetraazacyclotetradecane (TMC) have been studied by Spectrophotometric and calorimetric techniques. The spectra in dif

Metal Complexes with Macrocyclic Ligands
Metal Complexes with Macrocyclic Ligands, XVIII. A study of steric effects in the Co2+-, Ni2+- and Cu2+-complexes with 1-(2-aminoethyl)- and 1-(2-dimethylaminoethyl)-4,8,11-trimethyl-1,4,8,11-tetraazacyclotetradecane
✍ Arup. K. Basak; Thomas A. Kaden 📂 Article 📅 1983 🏛 John Wiley and Sons 🌐 German ⚖ 395 KB 👁 1 views

## Abstract The two macrocycles 1‐(2‐aminoethyl)‐ and 1‐[2‐(dimethylamino)ethyl]‐4, 8, 11‐trimethyl‐1, 4, 8, 11‐tetraazacyclotetradecane, **1** and **2**, respectively, and their metal complexes with Co^2+^, Ni^2+^ and Cu^2+^ were prepared. The different spectral properties of the complexes with th