𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Accurate determination and analysis of the temperature dependence of long-range spin–spin couplings in 2-chlorobenzaldehyde

✍ Scribed by Reino Laatikainen; Kari Tuppurainen; Yrjö Hiltunen; Simo Lötjönen

Publisher
John Wiley and Sons
Year
1990
Tongue
English
Weight
607 KB
Volume
28
Category
Article
ISSN
0749-1581

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

The proton‐proton spin‐spin couplings of 2‐chlorobenzaldehyde were determined accurately for acetone‐d~6~ and CD~3~CN solutions at several temperatures. The sign and temperature dependence of the para‐benzylic six‐bond coupling, ^6^J~α4~, was also obtained, although the observed value of this indicator of the formyl–ring co‐planarity was in the range −24 to −31 mHz. The fitting of the temperature dependence suggests that ^6^J~0~ (the value of the coupling when the formyl‐ring dihedral angle is 0°) is very small and probably positive, in contrast, for example, to styrene. The results are discussed on the basis of some modified INDO/FP calculations. A simple resolution enhancement technique is also described.

📜 SIMILAR VOLUMES

Long-range 13C1H spin—spin coupling cons
Long-range 13C1H spin—spin coupling constants in the conformational analysis of formyl derivatives of furan and thiophene
✍ Rois Benassi; Ugo Folli; Adele Mucci; Luisa Schenetti; Ferdinando Taddei 📂 Article 📅 1987 🏛 John Wiley and Sons 🌐 English ⚖ 672 KB

Long-range coupling constants, "J(C, H), involving the formyl proton or carbon and the carbons or protons of the heterocyclic ring, were measured in the two isomeric formyl-furans and -thiophenes by employing coupled 13C NMR spectra. In furan-2-carboxaldehyde these coupling constants, obtained in so

Long-range proton–proton spin–spin coupl
Long-range proton–proton spin–spin coupling constants in some aryl-substituted methylenemalonaldehydes. Conformational dependence of meta- and ortho-benzylic couplings in styrenoic systems
✍ E. Kolehmainen; R. Laatikainen; V. Král 📂 Article 📅 1986 🏛 John Wiley and Sons 🌐 English ⚖ 618 KB

The 'H N M R spectra of some aryl-and heteroaryl-substituted methylenemalonaldehydes were measured and analysed. The long-range proton-proton spin-spin coupling constants were used to estimate the conformational behaviour of the aryl group relative to the vinyl and aldehyde groups. The compounds ser

A DFT and AIM analysis of the spin–spin
A DFT and AIM analysis of the spin–spin couplings across the hydrogen bond in the 2-fluorobenzamide and related compounds
✍ Ibon Alkorta; José Elguero; Hans-Heinrich Limbach; Ilja G. Shenderovich; Tammo W 📂 Article 📅 2009 🏛 John Wiley and Sons 🌐 English ⚖ 216 KB

## Abstract In 1975 a large number of coupling constants were measured in 2‐fluorobenzamide labeled with ^15^N. Some of them were assigned to couplings through intramolecular NH···F hydrogen bonds (HBs). These couplings change dramatically when CDCl~3~ is replaced by DMSO‐__d__~6~. In this theoret