Preparation of enantiomerically pure p-substituted phenylethyl hydroperoxides by kinetic resolution and their use as enantioselective oxidants in the asymmetric Weitz-Scheffer epoxidation of E-chalcone
Özet
The kinetic resolution of a variety of secondary para-substituted phenylethyl hydroperoxides by Raphanus sativus L (black radish peroxidase) in the presence of guaiacol is reported. The peroxidase enzyme recognized (R)-configured alkyl aryl hydroperoxides, which furnished optically active (S)-hydroperoxides and (R)-alcohols. Kinetic resolution of tertiary hydroperoxides by the enzyme was unsuccessful. This study also shows how the optically active p-substituted (S)-hydroperoxides obtained can be employed as enantioselective oxidants in the asymmetric Weitz-Scheffer epoxidation of E-chalcone in the presence of KF-Al2O3 as a base. In all cases, a chalcone epoxide with the (alpha S,beta R)-configuration was obtained as the major isomer. Under the optimized reaction conditions, the enantiomeric excess of the chalcone epoxide was obtained in up to 49% in CH3CH at -40 degrees C. (C) 2012 Elsevier Ltd. All rights reserved.
Atıf için künye
Zilbeyaz, K., Kılıç, H., ŞİŞECİOĞLU, M., Özdemir, H., & Güngör, A. A. (2012). Preparation of enantiomerically pure p-substituted phenylethyl hydroperoxides by kinetic resolution and their use as enantioselective oxidants in the asymmetric Weitz-Scheffer epoxidation of E-chalcone. TETRAHEDRON-ASYMMETRY, 23(8), 594–601. https://doi.org/10.1016/j.tetasy.2012.04.005
BibTeX
@article{zilbeyaz2012-67368,
author = {Zilbeyaz, Kani and Kılıç, Hamdullah and ŞİŞECİOĞLU, Melda and Özdemir, Hasan and Güngör, Azize Alayli},
title = {Preparation of enantiomerically pure p-substituted phenylethyl hydroperoxides by kinetic resolution and their use as enantioselective oxidants in the asymmetric Weitz-Scheffer epoxidation of E-chalcone},
journal = {TETRAHEDRON-ASYMMETRY},
year = {2012},
volume = {23},
number = {8},
pages = {594--601},
issn = {0957-4166},
doi = {10.1016/j.tetasy.2012.04.005},
url = {https://akademik.atauni.edu.tr/yayinlar/67368-preparation-of-enantiomerically-pure-p-substituted-phenylethyl-hydroperoxides-by}
}