Solution Equilibria of Enantiopure Helicates: The Role of Concentration, Solvent and Stacking Interactions in Self-Assembly

Abstract

Many and varied are the effects which control the self‐assembly of silver helicates, as illustrated schematically: besides the structure of the ligand and the coordination preferences of the metal, conditions such as the nature of the solvent and the concentration may also exert an influence.

Chiral Self‐Recognition and Self‐Discrimination of Strapped Perylene Bisimides by π‐Stacking Dimerization

“…Most of the known examples for chiral recognition are based on the rather strong “inorganic” metal–ligand5a–c, 6a–f and cation–anion interactions,8 whereas examples based on weak “organic” interactions like hydrogen bonding and π–π interactions remain relatively rare 5d,e. 6g, h Notably, some interesting examples of self‐association by metal‐ion coordination or hydrogen bonding have been reported for chiral helicates,9 calix[4]arenes,10 and peptides 11…”

Multidimensional Mass Spectrometry Assisted Metallo-Supramolecular Chemistry

“…According to the concept of dynamic combinatorial library proposed by Lehn, 141 the self-assembly can be tuned by manipulating the external factors, including the stiffness of the ligand backbone, 30,142 counterions, [143][144][145] concentration, 146,147 temperature, 148,149 etc. However, it is challenging to clearly characterize such a library by NMR or other spectroscopic analyses with high requirement for purity.…”

18 Supramolecular coordination chemistry

“…Mixed Cu /Ag helicates were also prepared, and the chiroptical properties of all of the complexes were studied. 8 In the helical dimers [Cu I 2 (L 7 ) 2 ] 2 the coordination mode of the ligand, and in particular the way in which the three donor atoms are shared between two metals, depends on the nature of the substituent R. 9 [Ag 2 (L 8 ) 2 ] 2 is a double helicate in which the nitroxide radicals are ferromagnetically coupled within each ligand, but antiferromagnetically coupled between the two ligands of a complex cation. However the preference of Cu for four-coordination results in the ligand also providing bidentate binding domains in the mixed-valence complex [Cu II Cu I 3 (L 5 ) 2 ] 5 and in the pentanuclear complex [Cu I 5 (L 5 ) 2 ] 5 .…”

“…44 [ TiIV 4 (L 32 ) 6 ] 8À has a similar structure, but only in the presence of the Me 4 N cation which occupies the central cavity of the tetrahedron; in its absence, the triple helicate [Ti 2 (L 32 ) 3 ] 4À forms instead. 51 [Pd 8 (m-L 37 ) 4 (CN) 8 ], in which each [L 37 ] 2À links four metal ions, is a D 4 -symmetric box with helical chirality (Fig. 45 An alternative tetrahedral cage structure is shown by [M II 4 (L 33 ) 4 ] 4 (M Mn or Zn), in which each triply bridging ligand spans one face of the metal tetrahedron (Fig.…”