Matrix-Specific Effects on Caffeine and Chlorogenic Acid Complexation in a Novel Extract of Whole Coffea arabica

Boris Nemzer1,2, John Edwards3, Diganta Kalita1

  • 1VDF FutureCeuticals, Inc., Momence, IL 60954, USA.

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While α protons of carboxylic acids absorb at 2–2.5 ppm, β protons absorb further upfield.
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In aromatic compounds, such as benzene, the circulation of (4n + 2) π-electrons sets up a diamagnetic or diatropic ring current around the perimeter of the molecule. This current induces a magnetic field that opposes the external field inside the ring and reinforces it on the outside. The protons in benzene are deshielded and exhibit high chemical shifts in the range 6.5–8.5 ppm. The shielding effect at the center of the ring is evident in complex aromatic molecules, such as...
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