Influence of Bulky N-Substituents on the Formation of Lanthanide Triple Helical Complexes with a Ligand Derived from Bis(benzimidazole)pyridine: Structural and Thermodynamic Evidence
作者:Gilles Muller、Jean-Claude G. Bünzli、Kurt J. Schenk、Claude Piguet、Gérard Hopfgartner
DOI:10.1021/ic001289o
日期:2001.6.1
X-ray structures of L(11) (monoclinic, P2(1), a = 13.4850(12) A, b = 12.0243(11) A, c = 16.4239(14) A, beta = 103.747(7) degrees ), [La(ClO(4))(2)(L(11))(2)](3)[La(ClO(4))(2)(H(2)O)(L(11))(2)](ClO(4))(4).15MeCN (1a, monoclinic, P2(1), a = 21.765(4) A, b = 30.769(6) A, c = 21.541(5) A, beta = 116.01(3) degrees ), and [Eu(L(11))(3)](ClO(4))(3).4.28MeCN (5a, monoclinic, P1, a = 14.166(3) A, b = 19.212(4) A
平面芳香族三齿配体2,6-双(1-S-新戊基苯并咪唑-2-基)吡啶(L(11))与Ln(III)(Ln = La-Lu)在乙腈中反应生成连续的配合物[Ln (L(11))(n)](3+)(n = 1-3)。但是,通过分光光度法和NMR滴定法确定的稳定性常数表明,不利于tris配合物的形成,La(III)和Eu(III)的log K(3)约为1,而较小的log K(3)则没有证据。 Lu(III)离子。L(11)的X射线结构(单斜晶,P2(1),a = 13.4850(12)A,b = 12.0243(11)A,c = 16.4239(14)A,beta = 103.747(7)度) ,[La(ClO(4))(2)(L(11))(2)](3)[La(ClO(4))(2)(H(2)O)(L(11))( 2)](ClO(4))(4).15MeCN(1a,单斜晶系,P2(1),a = 21.765(4)A,b