Enantiodiscrimination in NMR spectra and X-ray structures of diastereomeric salts of trans-4-(4-fluorophenyl)-3-hydroxymethyl-1-methylpiperidine with (S)-Mosher acid

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F02%3A00007020" target="_blank" >RIV/00216224:14310/02:00007020 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Enantiodiscrimination in NMR spectra and X-ray structures of diastereomeric salts of trans-4-(4-fluorophenyl)-3-hydroxymethyl-1-methylpiperidine with (S)-Mosher acid

Popis výsledku v původním jazyce

Signal anisochrony delta in NMR spectra of racemic trans-4-(4-fluorophenyl)-3-hydroxymethyl-1-methylpiperidine 1 induced on the formation of diastereomeric salt complexes with (S)-Mosher acid 2 showed a strong dependence on solvent polarity, concentration, stoichiometric ratio and enantiomeric composition. X-ray structures of the salts, 3a and 3b, revealed that the conformations of the protonated base in ion pairs are very similar with respect to interatomic distances, bond and torsion angles but the mutual orientation of counterions in ion pairs differs significantly. It is suggested that the conformations of transient diastereomeric complexes in solution, responsible for delta;, resemble those in solid state. Furthermore, ab initio calculations performed on the optimized X-ray geometries of both ion pairs showed that the free energy of 3a is lower than that of 3b. This implies that the association constant for the formation of 3a is higher than that of 3b.

Název v anglickém jazyce

Enantiodiscrimination in NMR spectra and X-ray structures of diastereomeric salts of trans-4-(4-fluorophenyl)-3-hydroxymethyl-1-methylpiperidine with (S)-Mosher acid

Popis výsledku anglicky

Signal anisochrony delta in NMR spectra of racemic trans-4-(4-fluorophenyl)-3-hydroxymethyl-1-methylpiperidine 1 induced on the formation of diastereomeric salt complexes with (S)-Mosher acid 2 showed a strong dependence on solvent polarity, concentration, stoichiometric ratio and enantiomeric composition. X-ray structures of the salts, 3a and 3b, revealed that the conformations of the protonated base in ion pairs are very similar with respect to interatomic distances, bond and torsion angles but the mutual orientation of counterions in ion pairs differs significantly. It is suggested that the conformations of transient diastereomeric complexes in solution, responsible for delta;, resemble those in solid state. Furthermore, ab initio calculations performed on the optimized X-ray geometries of both ion pairs showed that the free energy of 3a is lower than that of 3b. This implies that the association constant for the formation of 3a is higher than that of 3b.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CC - Organická chemie

OECD FORD obor

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Projekt

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Návaznosti

Z - Vyzkumny zamer (s odkazem do CEZ)

Rok uplatnění

2002

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

J. Chem. Soc. Perkin Trans. 2

ISSN

1472-779X

e-ISSN

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Svazek periodika

2002

Číslo periodika v rámci svazku

12

Stát vydavatele periodika

CZ - Česká republika

Počet stran výsledku

7

Strana od-do

2093

Kód UT WoS článku

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EID výsledku v databázi Scopus

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