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Updated: May 9, 2026

Single-Molecule Förster Resonance Energy Transfer Methods for Real-Time Investigation of the Holliday Junction Resolution by GEN1
Published on: September 18, 2019
Unusual through-space, TS, pathway for the transmission of J(FHf) coupling: 2-fluorobenzaldehyde study case
Denize C Favaro1, Rubén H Contreras, Cláudio F Tormena
1Chemistry Institute, University of Campinas-UNICAMP, P.O. Box: 6154, 13084-862 Campinas, Sao Paulo, Brazil.
Abstract:
The (1)H NMR spectra of the title compound in nonpolar and polar solvents and theoretical calculation of spin-spin coupling constants (SSCCs) show that (TS)J(FHf) SSCC, where TS stands for "through-space", in polar solvents is amenable to measurement only in the trans conformer. The mechanisms for transmission pathways to such unusual SSCCs are rationalized in terms of the molecular electronic structure. It is stressed that such a result calls for some caution when intending to use (TS)J(FH) as a probe to detect the spatial proximity between fluorine and hydrogen atoms.
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