Olefination of α,α′-Divinyl Ketones through Catalytic Meyer−Schuster Rearrangement
作者:Curtis J. Rieder、Karl J. Winberg、F. G. West
DOI:10.1021/jo101497f
日期:2011.1.7
followed by catalytic Meyer−Schuster rearrangement has been developed for the olefination of 1,4-pentadien-3-ones to afford [3]dendralenes. Many of the traditional methods for the Meyer−Schuster rearrangement of alkynyl carbinols are not suitable with these highly unsaturated substrates because of their acid sensitivity. Unexpected reactivity during attempted rearrangement, including Nazarov-type electrocyclizations
Formal Homologous Aldol Reactions: Interrupting the Nazarov Cyclization via Carboalkoxylation of Alkynes
作者:Yen-Ku Wu、F. G. West
DOI:10.1021/ol500914a
日期:2014.5.2
Reactions between 1,4-pentadien-3-ones and aryl acetylenes in the presence of BF3·OEt2 furnish α-phenacyl cyclopentanones via a domino electrocyclization/carboalkoxylation reaction sequence. The overall process underscores a new mode of interruptedNazarov trapping, where two new carbon–carbon bonds are installed with concomitant formation of carbonyl functionality.
作者:Yonghoon Kwon、Robert McDonald、Frederick G. West
DOI:10.1002/anie.201303996
日期:2013.8.12
InternAl delivery: Organoaluminum reagents activate 1,4‐dien‐3‐ones for Nazarov electrocyclization (see scheme), then transfer a substituent to the resulting cyclopentenyl cation with moderate to complete regioselectivity and diastereoselectivity.
Intercepting the Nazarov Oxyallyl Intermediate with α-Formylvinyl Anion Equivalents to Access Formal Morita–Baylis–Hillman Alkylation Products
作者:F. West、Yen-Ku Wu、Rongrong Lin
DOI:10.1055/s-0036-1588769
日期:2017.7
catalyzed cationicdomino reaction involving sequential electrocyclization and polar addition of allenol ethers onto the resulting oxyallyl species is described. The overall sequence allows a highly stereoselective synthesis of densely substituted cyclopentanoid compounds containing α-formylvinyl functionality which is formally equivalent to products of a Morita–Baylis–Hillman alkylation process.
Interrupting Nazarov Reaction with Different Trapping Modality: Utilizing Potassium Alkynyltrifluoroborate as a σ-Nucleophile
作者:Ronny William、Siming Wang、Asadulla Mallick、Xue-Wei Liu
DOI:10.1021/acs.orglett.6b01606
日期:2016.9.16
cation intermediate generated following Nazarov cyclization of dienone has been successfully intercepted with potassium alkynyltrifluoroborates which act as σ-nucleophiles in the presence of BF3·Et2O. This new trapping modality allowed unprecedented introduction of an alkynyl moiety to the cyclopentanone framework by means of an interruptedNazarovreaction. The α-alkynyl cyclopentanone product can