Selection Rules for Helicate Ligand Component Self-Assembly: Steric, pH, Charge, and Solvent Effects

The reaction between 1,10-phenanthroline-2,9-dicarboxaldehyde, copper(I), and certain primary
amines was found to give quantitatively a dicopper double-helicate product (two of which were
crystallographically characterized) by imine self-assembly around CuI templates. The parameters of this
reaction were investigated, and important roles were found to be played by (i) the steric bulk of the amine,
(ii) the charge of the amine, (iii) the solvent used, and (iv) the pH of the solution. Water was found to allow
the broadest range of structures to form, and ligand-component exchange reactions (involving the substitution
of an aromatic for an aliphatic amine) were demonstrated to proceed readily in this solvent.

研究发现，1,10-菲绕啉-2,9-二羧醛、一价铜离子与某些一级胺之间的反应可定量地生成一种二铜双螺旋产物（其中两种通过晶体学方法进行了表征），该产物是通过围绕CuI模板的亚胺自组装形成的。本研究对反应参数进行了调查，发现胺的立体体积（i）、胺的电荷（ii）、所用的溶剂（iii）以及溶液的pH值（iv）在其中扮演了重要的角色。研究发现，水允许形成最广泛的结构范围，并且在此溶剂中，配体-组分交换反应（涉及芳胺对脂肪胺的取代）被证明可以轻易进行。