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Long range H,H coupling constants in cycloheptatrienes
Author(s) -
Günther Harald,
Görlitz Manfred
Publication year - 1974
Publication title -
organic magnetic resonance
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.483
H-Index - 72
eISSN - 1097-458X
pISSN - 0030-4921
DOI - 10.1002/mrc.1270060706
Subject(s) - sign (mathematics) , coupling constant , chemical shift , spectral line , physics , chemistry , spin (aerodynamics) , range (aeronautics) , coupling (piping) , spectrum (functional analysis) , nuclear magnetic resonance , atomic physics , stereochemistry , materials science , particle physics , mathematics , quantum mechanics , thermodynamics , mathematical analysis , metallurgy , composite material
The 1 H NMR spectra of 1,6‐dicarbomethoxycyclohepta‐1,3,5‐triene ( 2 ) and 3,4‐benzocyclohepta‐1,3,5‐triene ( 3 ) have been analysed in terms of chemical shifts and coupling constants. A method for the assignment of δ(AA′) and δ(BB′) in AA′BB′ systems, based on the observation of 13 C satellites in the 1 H NMR spectrum, is described. For J (1,5) in 3 , a negative sign was established. Spin tickling experiments were used to determine the positive sign for J (2,5) in 2 and the negative sign for J (2,7) in 3. The conformation of 3 is discussed.