Substituent effects on aromatic stacking interactions.
Synthetic supramolecular zipper complexes have been used to quantify substituent effects on the free energies of aromatic stacking interactions. The conformational properties of the complexes have been characterised using NMR spectroscopy in CDCl(3), and by comparison with the solid state structures of model compounds. The structural similarity of the complexes makes it possible to apply the double mutant cycle method to evaluate the magnitudes of 24 different aromatic stacking interactions. The major trends in the interaction energy can be rationalised using a simple model based on electrostatic interactions between the pi-faces of the two aromatic rings. However, electrostatic interactions between the substituents of one ring and the pi-face of the other make an additional contribution, due to the slight offset in the stacking geometry. This property makes aromatic stacking interactions particularly sensitive to changes in orientation as well as the nature and location of substituents.
Cockroft
Scott L
SL
Centre for Chemical Biology, Department of Chemistry, Krebs Institute for Biomolecular Science, University of Sheffield, Sheffield, UK.
Perkins
Julie
J
Zonta
Cristiano
C
Adams
Harry
H
Spey
Sharon E
SE
Low
Caroline M R
CM
Vinter
Jeremy G
JG
Lawson
Kevin R
KR
Urch
Christopher J
CJ
Hunter
Christopher A
CA
D000814:Aniline Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D001665:Binding Sites; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D010795:Phthalic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D012680:Sensitivity and Specificity; D013237:Stereoisomerism
D000814:Aniline Compounds; D010795:Phthalic Acids; C059768:isophthalate