論文

査読有り
2013年4月

Critical profiles of chiral diether-mediated asymmetric conjugate aminolithiation of enoate with lithium amide as a key to the total synthesis of (-)-kopsinine

TETRAHEDRON
  • Shingo Harada
  • ,
  • Takeo Sakai
  • ,
  • Kiyosei Takasu
  • ,
  • Ken-ichi Yamada
  • ,
  • Yasutomo Yamamoto
  • ,
  • Kiyoshi Tomioka

69
15
開始ページ
3264
終了ページ
3273
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1016/j.tet.2013.02.035
出版者・発行元
PERGAMON-ELSEVIER SCIENCE LTD

Chiral diether-mediated asymmetric aminolithiation of indolylpropenoate with lithium amide in toluene at -78 degrees C for 15 min gave, after aqueous ammonium chloride quench, the corresponding conjugate addition product with 97% ee in 89% yield. If hydrogen chloride in methanol was selected as a quencher, however, aminolithiation at -78 degrees C for 3 h gave the corresponding adduct with 97% ee in 54% yield, along with recovery of the starting enoate in 39% yield. Based on this finding of an incomplete and slow reaction at -78 degrees C, the aminolithiation conditions were optimized to be at -60 degrees C for 15 h and subsequent enolate trap with alkyl halide upon an addition of DMPU afforded the desired aminoalkylation product with 98% ee in 89% yield. Further approach toward total synthesis of (-)-kopsinine was carried out by examining asymmetric aminolithiation with N-hydroxyethylamine equivalent, one-pot piperidine formation, and Claisen condensation. (C) 2013 Elsevier Ltd. All rights reserved.

リンク情報
DOI
https://doi.org/10.1016/j.tet.2013.02.035
J-GLOBAL
https://jglobal.jst.go.jp/detail?JGLOBAL_ID=201302207107225437
CiNii Articles
http://ci.nii.ac.jp/naid/120005244223
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000316582400018&DestApp=WOS_CPL
URL
http://www.scopus.com/inward/record.url?eid=2-s2.0-84875231708&partnerID=MN8TOARS
URL
http://orcid.org/0000-0002-1798-7919
ID情報
  • DOI : 10.1016/j.tet.2013.02.035
  • ISSN : 0040-4020
  • J-Global ID : 201302207107225437
  • CiNii Articles ID : 120005244223
  • ORCIDのPut Code : 45409565
  • SCOPUS ID : 84875231708
  • Web of Science ID : WOS:000316582400018

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