A short and efficient asymmetric synthesis of (−)-frontalin, (−)-exo-isobrevicomin and a volatile contributor of beer-aroma
作者:Surendra Singh、Patrick J. Guiry
DOI:10.1016/j.tet.2010.05.032
日期:2010.7
The natural products, (−)-frontalin and (+)-exo-isobrevicomin were synthesized employing Sharpless asymmetric epoxidation and ZrCl4-catalyzed intramolecular acetalization as the key steps. (−)-Frontalin was synthesized in three steps with a 61.4% overall yield and 89.9% ee and (−)-exo-isobrevicomin also obtained in an overall satisfactory yield of 10.1% and 97% ee. We have also synthesized the volatile
gem-Dihydroperoxides were successfully used for the enantioselective epoxidation of tertiary and primary allylic alcohols. Epoxides derived from tertiary alcohols were obtained in yields up to 71% with ee's up to 52%. (c) 2013 Elsevier Ltd. All rights reserved.
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