Interplay of interactions governing the dynamic conversions of acyclic and macrocyclic helicates.
A rigid, helical macrocycle that contains two copper(I) ions has been synthesized through subcomponent self-assembly. Although it does not obey the "rule of coordinative saturation", this macrocycle could be prepared through subcomponent substitution starting from a tri(copper(I)) helicate, in a reaction in which copper(I) was ejected. The macrocycle was observed to readily participate in a sequence of transformations between helical structures mediated by the electronic effects of substituents, entropic effects, the conformational preferences of organic building blocks, and the coordinative preferences of the metal ion. The thermodynamic parameters governing the interconversion of an "open" helicate and the "closed" macrocycle were determined through van 't Hoff analysis, allowing quantification of the entropic driving force for macrocyclization.
Campbell
Victoria E
VE
Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
de Hatten
Xavier
X
Delsuc
Nicolas
N
Kauffmann
Brice
B
Huc
Ivan
I
Nitschke
Jonathan R
JR
D002384:Catalysis; D003300:Copper / Q000737:chemistry; D018360:Crystallography, X-Ray; D006839:Hydrocarbons, Acyclic / Q000138:chemical synthesis* / Q000737:chemistry; D047028:Macrocyclic Compounds / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D013816:Thermodynamics
D006839:Hydrocarbons, Acyclic; D047028:Macrocyclic Compounds; D009942:Organometallic Compounds; D003300:Copper