Dinuclear complexes of a pseudocalixarene macrocycle: structural consequences of intramolecular hydrogen bonding.
A series of dinuclear complexes of a pseudocalixarene macrocycle H6L containing two 2,2'-methylenediphenol groups have been synthesised and structurally characterised. Using divalent metal ions, complexes containing a common hyperbolic paraboloid (saddle) M2(H4L)2+ core are formed. The structure is controlled by two strong O-H-O interactions resulting from metal ion-promoted monodeprotonation of the methylenediphenol units. The metal ions are located in a cleft within which neutral or anionic guests can bind. Use of trivalent metal ions leads to complete deprotonation of the phenol groups and loss of the saddle conformation.
Fontecha
Julia Barreira
JB
Chemistry Department, Loughborough University, Loughborough, UK LE11 3TU.
Goetz
Sandrine
S
McKee
Vickie
V