Zinc and cadmium complexes with an achiral symmetric helicand. Crystal structure of an enantiomerically pure Λ-Zn(<scp>ii</scp>) monohelicate
作者:Manuel R. Bermejo、Miguel Vázquez、Jesús Sanmartín、Ana M. García-Deibe、Matilde Fondo、Carlos Lodeiro
DOI:10.1039/b201433p
日期:——
Zn(II) and Cd(II) complexes with an N-tosyl substituted N4-donor Schiff base, containing a 2-propanol residue as spacer, have been prepared. The X-ray crystal structure of the monohelicate Î-Zn(OHPTs)·H2O [H2OHPTs: N,Nâ²-bis(2-tosylaminobenzylidene)-1,3-diamino-2-propanol] has been solved. The Zn(II) ion assumes a distorted tetrahedral coordination geometry, involving the four donor N atoms of the bisdeprotonated ligand. Strong (OâHâ¯O) hydrogen bonds between neighbouring complex and lattice water molecules lead to intricate intermolecular interactions that seem to drive the crystal packing. This Zn(II) complex shows an intense blue fluorescence in solution (λâ=â430 nm, Ïâ=â0.14), which is also observed in the solid state (λâ=â490 nm). Cd(OHPTs)·4H2O, although at a lower level (Ïâ=â0.08), is also luminescent (λâ=â430 nm) in acetonitrile solution.
已制备含有2-丙醇残基作为间隔的N-托烷基取代的N4供体Schiff碱的Zn(II)和Cd(II)复合物。单水合物Î-Zn(OHPTs)·H2O(H2OHPTs:N,Nâ²-双(2-托烷基氨基苯亚甲基)-1,3-二氨基-2-丙醇)的X射线晶体结构已被解析。Zn(II)离子呈现出扭曲的四面体配位几何结构,涉及双去质子化配体的四个供体N原子。相邻复合物与晶格水分子之间的强(O–H···O)氢键导致复杂的分子间相互作用,这似乎推动了晶体的堆积。该Zn(II)复合物在溶液中表现出强烈的蓝色荧光 (λ=430 nm, ε=0.14),在固态中也有观察到 (λ=490 nm)。Cd(OHPTs)·4H2O虽然发光强度较低 (ε=0.08),但在乙腈溶液中也具有发光性 (λ=430 nm)。