H-bond cooperativity: polarisation effects on secondary amides

Abstract

Formation of an intramolecular phenol-amide H-bond leads to a dramatic increase in the H-bond donor strength of the amide NH group. Polarisation of the amide group is directly proportional to the polarity of the phenol H-bond donor.

Polarisation effects on the H-bond acceptor properties of secondary amides

“…We have previously measured the effect of an intramolecular interaction between a phenol H-bond donor and an amide carbonyl oxygen on the H-bond donor properties of the amide NH donor interacting with a phosphine oxide (R 3 PO). 21 A linear relationship was found between the value of a for the phenol and the value of a for the amide, and the slope of this correlation was also 0.2.…”

Control of the assembly of a cyclic hetero[4]pseudorotaxane from a self-complementary [2]rotaxane

“…3b ). The employment of DMSO, a highly polar solvent able to strongly compete for the establishment of hydrogen-bonding interactions, 28 apparently precluded the assembly of the supramolecular aggregate 5·5 occurring in CDCl 3 . Thus, the formation or not of the supramolecular dimer can be controlled by selecting media of different polarity, the use of a very polar solvent such as DMSO completely precluding the assembly ( Fig.…”

The interplay between hydrogen and halogen bonding: substituent effects and their role in the hydrogen bond enhanced halogen bond

“…6–8 We used Hammett parameters to analyze possible inductive (or field effects as proposed by Wheeler and Houk 30 ) and resonance effects on the HBeXB receptor binding—an approach recently used by Hunter to effectively assess HB cooperativity. 31…”