Indirect Nonbonded Nuclear Spin-Spin Coupling: A Guide for the Recognition and Understanding of "Through-Space" NMR J Constants in Small Organic, Organometallic, and Coordination Compounds

Indirect nuclear spin-spin coupling involving very commonly encountered nuclei such as 1H, 13C, 19F, or 31P provides definitive data for characterization of molecules in solution. Nonbonded spin coupling characterized by high magnitude values have been repeatedly authenticated for a range of compounds such as functionalized cyclophanes, naphthalenes, coordination complexes of polyphosphines, as well as fluorinated arene complexes. The range of applications in chemistry and structural biology involving a 19F NMR probe proves that TS spin coupling with this nucleus can be a valuable additional tool in pursuing structural questions. Analysis of TS 19F coupling in fluorinated organic molecules, but also in amino acids, proteins, nucleic acids, and nucleic acid-protein complexes can inform us regarding the differentiation of rotamers and diastereoisomers, estimation of internuclear distances, computation of tertiary and quaternary structures, as well as understanding of dynamic processes involved in solution.