Tandem alkylation–cyclization process via an O,C-dianion
摘要:
A general protocol for preparing densely functionalized cyclopentenones through a tandem nucleophilic addition-deprotonation-alkylation-cyclization process is described. Addition of lithioallene 2 to enamides 1 generates tetrahedral intermediate 3. Deprotonation of the gamma carbon atom of the allene function in situ, followed by trapping by a suitable electrophile and cyclization during workup leads to C6 substituted cyclopentenones 6. (c) 2005 Elsevier Ltd. All rights reserved.
Asymmetric Cyclopentannelation. Chiral Auxiliary on the Allene
作者:Paul E. Harrington、Marcus A. Tius
DOI:10.1021/ol0001362
日期:2000.8.1
An enantioselective variant of the synthesis of cross-conjugated cyclopentenones, based on D-glucose-derived chiral auxiliaries, is described. Minor modification of the method makes it applicable to the preparation of both enantiomeric series of products. Both enantiomers of the key intermediate in our roseophilin synthesis have been prepared.
Cobalt-Catalyzed Reductive Carboxylation of α,β-Unsaturated Compounds with Carbon Dioxide
作者:Chika Hayashi、Takuo Hayashi、Tohru Yamada
DOI:10.1246/bcsj.20150043
日期:2015.6.15
The gaseous carbon dioxide incorporation reaction with α,β-unsaturated compounds was examined in the presence of a catalytic amount of bis(acetylacetonato)cobalt(II) and using diethylzinc as a redu...
在催化量的双(乙酰丙酮)钴 (II) 存在下,并使用二乙基锌作为还原剂,研究了气态二氧化碳与 α,β-不饱和化合物的掺入反应。
Reagent-free Nazarov cyclisations
作者:Frederic Douelle、Lauren TalVisiting undergraduate from Barn、Michael F. Greaney
DOI:10.1039/b415463k
日期:——
A new protocol for Nazarov cyclisation is described that involves simple heating of dienones in the absence of any external Lewis acid.
描述了一种新的纳扎罗夫环化方案,该方案涉及在没有任何外部路易斯酸的情况下简单加热二烯酮。
The First Example of Nazarov Reactions of Vinyl Cumulenyl Ketones
作者:Eric Leclerc、Marcus A. Tius
DOI:10.1021/ol034110x
日期:2003.4.1
[reaction: see text] alpha-Lithio cumulenyl ethers can be prepared in situ and converted to alpha-allenyl cyclopentenones. Isomerization of the product of one such reaction has led to a furanyl cyclopentenone, the core structure of nakadomarin A.