Conformational stability of atropisomeric 1-naphthylcarbinols and 1-(1-naphthyl)ethylamines

Tetrahedron Letters

Volumn 43, Issue 47, 2002, Pages 8563-8567

  Wolf, Christian ^a   Pranatharthiharan, Lakshmi ^a   Ramagosa, Ryan B ^a  

^a GEORGETOWN UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

1 (1 NAPHTHYL) 2,2 DIMETHYL 1 PROPANOL; ETHYLAMINE; METHANOL DERIVATIVE; N,N' DIBUTYL 1 (1 NAPHTHYL)ETHYLAMINE; NAPHTHALENE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CHIRALITY; CONFORMATION; HIGH PERFORMANCE LIQUID CHROMATOGRAPHY; ISOMER; ISOMERISM; KINETICS; MOLECULAR STABILITY; NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; ROOM TEMPERATURE; SEPARATION TECHNIQUE; STRUCTURE ACTIVITY RELATION;

EID: 0037131765     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(02)02092-0     Document Type: Article

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24. Diastereoisomers of alcohol 3 were resolved on (S,S)-Whelk-O 1 or on phenylglycine using hexanes/EtOH (98:2) as the mobile phase at 25°C (diastereoselectivity α=1.5 and 1.2, respectively). Since the separation of conformational isomers of 3 was accomplished employing chiral stationary phases one could assume that indeed enantiomers were resolved. However, this can be ruled out due to different UV spectra observed for the separated isomers.
25. The rate constant and rotational energy barrier of isomerization were calculated according to the formalism of reversible first-order reactions. The accuracy of the free energy barrier to rotation of 3 determined in this study was limited to ±2 kJ/mol due to temperature fluctuations of ±5°C.
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