AbstractsChemistry

Isotope effects on chemical shifts in the study of intramolecular hydrogen bonds

by Poul Erik Hansen




Institution: Roskilde University
Department:
Year: 2015
Keywords: intramolecular hydrogen bonding; isotope effects; NMR; hydrogen bonding; isotope effects; NMR
Record ID: 1120006
Full text PDF: http://rudar.ruc.dk/handle/1800/22893


Abstract

The paper deals with the use of isotope effects on chemical shifts in characterizing intramolecular hydrogen bonds. Both so-called resonance-assisted (RAHB) and non-RAHB systems are treated. The importance of RAHB will be discussed. Another very important issue is the borderline between “static” and tautomeric systems. Isotope effects on chemical shifts are particularly useful in such studies. All kinds of intramolecular hydrogen bonded systems will be treated, typical hydrogen bond donors: OH, NH, SH and NH+, typical acceptors C=O, C=N, C=S C=N−. The paper will be deal with both secondary and primary isotope effects on chemical shifts. These two types of isotope effects monitor the same hydrogen bond, but from different angles; The paper deals with the use of isotope effects on chemical shifts in characterizing intramolecular hydrogen bonds. Both so-called resonance-assisted (RAHB) and non-RAHB systems are treated. The importance of RAHB will be discussed. Another very important issue is the borderline between “static” and tautomeric systems. Isotope effects on chemical shifts are particularly useful in such studies. All kinds of intramolecular hydrogen bonded systems will be treated, typical hydrogen bond donors: OH, NH, SH and NH+, typical acceptors C=O, C=N, C=S C=N−. The paper will be deal with both secondary and primary isotope effects on chemical shifts. These two types of isotope effects monitor the same hydrogen bond, but from different angles