Trialkyl Methanetricarboxylate as Dialkyl Malonate Surrogate in Copper-Catalyzed Enantioselective Propargylic Substitution
摘要:
The first copper-catalyzed enantioselective propargylation of trialkyl methantricarboxylate with propargylic alcohol derivatives was developed. The tricarboxylate unit in the obtained adducts could be easily transformed into a malonate moiety by treating with in situ generated NaOEt in excellent yield without racemization.
Gold-Catalyzed Cyclopenta- and Cycloheptannulation Cascades: A Stereocontrolled Approach to the Scaffold of Frondosins A and B
作者:David Garayalde、Karolin Krüger、Cristina Nevado
DOI:10.1002/anie.201006105
日期:2011.1.24
Golden cascades: Two diastereoselective gold‐catalyzed cascade processes in which propargyl acetates react with alkenes or 1,4‐dienes afford highly substituted five‐ and seven‐membered rings, respectively (see scheme). The concerted nature of the gold‐catalyzed Cope rearrangement has been used in the formal enantioselective synthesis of marine norsesquiterpenoids Frondosins A and B.
Gold Catalysis: Highly Functionalized Cyclopentadienes Prepared by Intermolecular Cyclization of Ynamides and Propargylic Carboxylates
作者:Eva Rettenmeier、Andreas M. Schuster、Matthias Rudolph、Frank Rominger、Christoph A. Gade、A. Stephen K. Hashmi
DOI:10.1002/anie.201301382
日期:2013.5.27
When an ynamide meets a gold carbenoid: Highly electrophilic gold carbenoids available from propargylic esters by means of 1,2‐acyloxy migration open up new reaction pathways for ynamidegold chemistry. In this way highlyfunctionalizedcyclopentadiene derivatives become accessible (see scheme; EWG=electron‐withdrawing group).
Difluorocarbene generated from FSO2CF2CO2SiMe3 (TFDA) at 120 °C could reacted with terminalalkynes having an ester group at the αposition to the triplebond. Difluorocyclopropenes were further converted to difluorocyclopropyl ketones under alkaline condition. Mechanism for the conversion was studied.
由FSO 2 CF 2 CO 2 SiMe 3(TFDA)在120°C下生成的二氟卡宾可以与在三键的α位具有酯基的末端炔烃反应。在碱性条件下,将二氟环丙烯进一步转化为二氟环丙基酮。研究了转化机理。
Synthesis of Azepines by a Gold-Catalyzed Intermolecular [4 + 3]-Annulation
作者:Nathan D. Shapiro、F. Dean Toste
DOI:10.1021/ja803890t
日期:2008.7.1
A convenient gold(III)-catalyzed synthesis of azepines from the intermolecular annulation of propargyl esters and alpha,beta-unsaturated imines is reported (19 examples, 55-95% yield). This formal [4 + 3]-cycloaddition reaction is proposed to proceed via a stepwise process involving intramolecular trapping of an allyl-gold intermediate.
Gold-Catalyzed Regioselective Synthesis of Crowded Cyclopentadienes by Migratory Cycloisomerization of Vinylallenes
作者:Olaya Bernardo、Javier González、Javier Borge、Luis A. López
DOI:10.1021/acs.orglett.2c02035
日期:2022.7.22
We report the regioselective synthesis of silyl-substituted cyclopentadienyl esters through gold-catalyzed migratory cycloisomerization of silyl-substituted vinylallenes. This transformation is proposed to proceed through a perfectly orchestrated sequence of events including Nazarov-like cyclization and several silyl and hydrogen rearrangements. Furthermore, exploiting the multifaceted nature of the