Influence of the length of the quaternisation group on the cyclometallation of [M(2,4′-R-bipy)Cl<sub>3</sub>](M = Pt<sup>II</sup>or Pd<sup>II</sup>; 2,4′-R-bipy = 1′-alkyl-2,4′-bipyridinium)
作者:Smita Wimmer、Franz L. Wimmer
DOI:10.1039/dt9940000879
日期:——
Solid-state thermolysis of the 1'-alkyl-2,4'-bipyridinium complexes [M(2,4'-R-bipy)Cl3] (M = Pd(II) or Pt(II); R = H, Me, Bu, C6H13, C8H17 or C10H21) gave the cyclometallated complexes [M(2,4'-R-bipy - H)Cl2] in quantitative yield. For M = Pd there is no clear variation of the cyclometallation temperature with the length of the alkyl chain, whereas the temperature of cycloplatination decreases steadily as the length of the alkyl chain increases. The extent of cyclometallation in aqueous solution depends on the solubility of the complex and decreases as the hydrophobicity of the chain increases.