About this Book

This chapter is devoted to the 1–3JCCs and to the factors influencing their magnitude. The experimental and calculated J data presented in the subsequent parts of the chapter are arranged with the thought of showing how hybridization, substituent electronegativity, the complex and hydrogen bond formation, and geometry of the compound bear on the JCC magnitude and which range of changes can be expected for a given type of coupling when all these effects are taken into account. The subsequent sections are devoted to the couplings across single, double, and triple CC bonds and to the couplings in aromatic and heteroaromatic systems and in the compounds of biological importance. It is also shown that at the present level of theory, it is possible in many cases to reproduce the experimental J values very exactly, achieving one-to-one correspondence.