An exceptionally short and simple enantioselective total synthesis of pentacyclic triterpenes of the β-amyrin family

Journal of the American Chemical Society

Volumn 121, Issue 43, 1999, Pages 9999-10003

  Huang, Alan X ^a   Xiong, Zhaoming ^a   Corey, E J ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BETA AMYRIN; BROMINE DERIVATIVE; LITHIUM DERIVATIVE; OLEANOLIC ACID; SILANE DERIVATIVE; TRITERPENE DERIVATIVE;

ARTICLE; CHEMICAL REACTION; CHEMICAL STRUCTURE; CYCLIZATION; SYNTHESIS;

EID: 0033520737     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja992411p     Document Type: Article

References (16)

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3. For other approaches to the synthesis of pentacyclic triterpenoids (racemic) using cation-π cyclization see: Fish, P. V.; Johnson, W. S. J. Org. Chem. 1994, 59, 2324.
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6. 2 with barium metal strips (prepared by hammering mineral oil covered Ba chunks into <1 mm thick sheets and cutting by scissors).
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11. Success in the CuCl-mediated ring closure to form 10 depends critically on removal of Pd species and LiCl from the vinyl tin substrate (readily accomplished by filtration of the crude material through a column of basic alumina).
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