New Entry to a Three-Component Pyrimidine Synthesis by TMS−Ynones via Sonogashira Coupling
作者:Alexei S. Karpov、Thomas J. J. Müller
DOI:10.1021/ol035212q
日期:2003.9.1
synthesized in an atom-economical fashion by coupling (het)aroyl chlorides and (TMS)-acetylene with only one equiv (!) of triethylamine under Sonogashira conditions. This mild ynone synthesis is also a suitable entry to 2,4-disubstituted pyrimidines in the sense of a one-pot three-component reaction, i.e., a coupling-addition-cyclocondensation sequence.
A Cascade Reaction of Michael Addition and Truce-Smiles Rearrangement to Synthesize Trisubstituted 4-Quinolone Derivatives
作者:Caixia Xie、Di Yang、Xinfeng Wang、Chen Ma
DOI:10.1021/acs.joc.0c01662
日期:2020.12.4
A novel transition-metal-free cascade reaction to synthesize 4-quinolone derivatives has been demonstrated. Michael addition and Truce-Smiles rearrangement are included in this protocol, providing a broad scope of 4-quinolones in moderate-to-excellent yields. This work serves as an example of the use of sulfonamides through Truce–Smiles rearrangement to build heterocyclic compounds under mild conditions
Remote Central-to-Axial Chirality Conversion: Direct Atroposelective Ester to Biaryl Transformation
作者:Achim Link、Christof Sparr
DOI:10.1002/anie.201803472
日期:2018.6.11
A strategy for the remote central‐to‐axial chiralityconversion by simultaneous planarization of an encoding and a transient stereocenter is presented. Based on a diastereoselective double addition of a chiral 1,5‐bifunctional organomagnesium alkoxide reagent to a broad range of aryl ester substrates, axially chiralbiaryls are directly obtained upon in situ reduction. Various structurally distinct
On the Structure of Intermediates in Enyne Gold(I)‐Catalyzed Cyclizations: Formation of
<i>trans</i>
‐Fused Bicyclo[5.1.0]octanes as a Case Study
作者:Imma Escofet、Helena Armengol‐Relats、Hanna Bruss、Maria Besora、Antonio M. Echavarren
DOI:10.1002/chem.202004237
日期:2020.12
The nature of cyclopropyl gold(I) carbene‐type intermediates has been reexamined as part of a mechanistic study on the formation of cis‐ or trans‐fused bicyclo[5.1.0]octanes in a gold(I)‐catalyzed cascade reaction. Benchmark of DFT methods together with QTAIM theory and NBO analysis confirms the formation of distinct intermediates with carbenic or carbocationic structures in the cycloisomerizations
β-Silyl-Assisted Tandem Diels–Alder/Nazarov Reaction of 1-Aryl-3-(trimethylsilyl) Ynones
作者:Rachael A. Carmichael、Punyanuch Sophanpanichkul、Wesley A. Chalifoux
DOI:10.1021/acs.orglett.7b00911
日期:2017.5.19
A one-pot tandem Diels–Alder/Nazarov reaction of 1-aryl-3-(trimethylsilyl) ynones has been achieved to generate carbo- and heterocyclic fused ring systems in good to excellent yields. The β-silyl effect is instrumental in accessing this otherwise challenging cascade annulation reaction. The tandem reaction proceeds in the presence of BCl3 to generate three new carbon–carbon bonds, a quaternary carbon