Synlett 2020; 31(02): 158-164
DOI: 10.1055/s-0039-1691498
letter
© Georg Thieme Verlag Stuttgart · New York

A New Approach Using Aromatic-Solvent-Induced Shifts in NMR Spectroscopy to Analyze β-Lactams with Various Substitution Patterns

Leticia Chavelas-Hernández
,
Jonathan R. Valdéz-Camacho
,
Luis G. Hernández-Vázquez
,
Blanca E. Dominguez-Mendoza
,
María G. Vasquez-Ríos
,
Consejo Nacional de Ciencia y Tecnología (CB2015/256653).
Further Information

Publication History

Received: 12 September 2019

Accepted after revision: 09 November 2019

Publication Date:
09 December 2019 (online)


Abstract

The chemical shifts of protons depend not only on the properties of the solute molecule but also on the medium in which the solute resides. A series of β-lactams with various substitution patterns were synthesized to study aromatic-solvent-induced shifts (ASISs) in chloroform and benzene by using 1H NMR spectroscopy. The results agreed with those obtained by theoretical density functional theory calculations. The protons of the β-lactam ring are the most affected by the ASIS effect, and they tend to overlap due to the anisotropic effect of benzene.

Supporting Information

 
  • References and Notes

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