Related Experiment Video
Updated: Jul 9, 2026

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Aromatic delta-peptides
Hua Jiang1, Jean-Michel Léger, Ivan Huc
1Institut Européen de Chimie et Biologie, 16 av. Pey Berland, 33607 Pessac Cedex, France.
Abstract:
Oligoamides of 8-amino-2-carboxy-quinoline adopt a very stable helical conformation characterized in solution by 1H NMR and in the solid state by single-crystal X-ray diffraction. The helix comprises only 2.5 units per turn, which represents the highest curvature achieved by aromatic oligoamides until now. Monomers possessing alkoxy substituents in position 4 are easily available from 2-nitroaniline and dimethyl acetylenedicarboxylate.
Related Concept Videos
VSEPR Theory and the Basic Shapes
VSEPR Theory and the Effect of Lone Pairs
Molecular Shape and Polarity
Hybridization of Atomic Orbitals I
Molecular Geometry and Dipole Moments
Radicals: Electronic Structure and Geometry
Accordingly, the structure of a trivalent radical lies between the geometries of carbocations and carbanions. An sp2-hybridized carbocation is trigonal planar, while an sp3-hybridized carbanion is trigonal pyramidal. Here, the difference in geometry is...

