Premium
Proximity Effects in Organic Chemistry—The Photoelectron Spectroscopic Investigation of Non‐Bonding and Transannular Interactions
Author(s) -
Martin HansDieter,
Mayer Bernhard
Publication year - 1983
Publication title -
angewandte chemie international edition in english
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.831
H-Index - 550
eISSN - 1521-3773
pISSN - 0570-0833
DOI - 10.1002/anie.198302831
Subject(s) - chemistry , intramolecular force , chromophore , ring (chemistry) , spectral line , crystallography , 2 norbornyl cation , computational chemistry , ground state , molecule , solvolysis , molecular orbital , cyclopropane , photochemistry , stereochemistry , organic chemistry , atomic physics , physics , astronomy , hydrolysis
Abstract Classical structural formulas often convey the impression only those relationships between the atoms are of importance which hold a molecule together as symbolized by the chemical bonds. However, many interactions between atoms or groups of atoms are not adequately denoted in this manner. Nevertheless, their existence can have important consequences for ground state energies ( cis ‐difluoroethylene is more stable than trans ‐difluoroethylene), conformations (the syn form of methyl vinyl ether is more stable than the anti form), reactivities (an endo cyclopropane ring in 7‐ anti ‐norbornyl derivatives accelerates solvolysis by a factor of 10 14 ), UV spectra (“superposition” of the π‐systems of acridine and purine‐bonded through a four‐membered chain‐results in hypochromism), CD spectra (the inherently symmetrical but dissymmetrically perturbed chromophore of 2‐deuterionorbornadiene allows the observation of three transitions in the near UV), and ESR spectra (the long‐range coupling with H‐4 in the bridgehead bicyclo[2.1.1]hex‐1‐yl radical equals 22.5 G). Since orbital interactions are involved in most intramolecular effects of this kind, photoelectron spectroscopy has proven an informative and valuable extension to other methods.