19F-NMR Diastereotopic Signals in Two N-CHF₂ Derivatives of (4S,7R)-7,8,8-Trimethyl-4,5,6,7-tetrahydro-4,7-methano-2H-indazole.
In this paper, we report the anisochrony of the fluorine atoms of a CHF₂ group when linked to a pyrazole ring. The pyrazole is part of (4S,7R)-7,8,8-trimethyl-4,5,6,7-tetrahydro-4,7-methano-2H-indazole also known as (4S,7R)-campho[2,3-c]pyrazole, which has two stereogenic centers. Gauge-Independent Atomic Orbital (GIAO)/Becke, 3-parameter, Lee-Yang-Parr (B3LYP)/6-311++G(d,f) calculated 19F chemical shifts of the minimum energy conformations satisfactorily agree with the experimental data. The energy differences between minima need to consider solvent effects (continuum model) to be satisfactorily reproduced.
['García-Pérez|Diana|D|', 'López|Concepción|C|0000-0002-2343-902X', 'Claramunt|Rosa M|RM|0000-0001-6634-2677', 'Alkorta|Ibon|I|0000-0001-6876-6211', 'Elguero|José|J|']
D005461:Fluorine D007191:Indazoles D009682:Magnetic Resonance Spectroscopy D008958:Models, Molecular D008968:Molecular Conformation D015394:Molecular Structure
diastereotopic anisochrony pyrazoles 19F‐NMR B3LYP GIAO PCM indazoles