Synergistic Gold and Iron Dual Catalysis: Preferred Radical Addition toward Vinyl–Gold Intermediate over Alkene
摘要:
A dual catalytic approach enlisting gold and iron, synergy is described. This method offers readily access to substituted heterocycle aldehydes via oxygen radical addition to vinyl-gold intermediates under Fe catalyst assistance. This system shows good functional group compatibility for the generation of substituted oxazole, indole, and benzofuran aldehydes. Mechanistic evidence greatly supports selective radical addition to an: activated vinyl-Au double bond over alkene. This unique discovery offers a new avenue with great potential to further extend the synthetic power and versatility of gold catalysis.
Preparation of Highly Functionalised Benzofurans from<i>ortho</i>-Hydroxyphenones and Dichloroethylene: Applications and Mechanistic Investigations
作者:Florian Schevenels、Bernard Tinant、Jean-Paul Declercq、István E. Markó
DOI:10.1002/chem.201201505
日期:2013.3.25
Highlyfunctionalisedbenzofurans have been prepared from ortho‐hydroxyphenones and 1,1‐dichloroethylene. The key intermediate, a chloromethylene furan, smoothly rearranged into the corresponding benzofuran carbaldehyde under acidic conditions. Some mechanisticinvestigations have been performed and several biologically active benzofurans have been synthesised.
Diphenyl-Diselenide-Mediated Domino Claisen-Type Rearrangement/Cyclization of Propargylic Aryl Ethers: Synthesis of Naphthofuran-2-carboxaldehyde Derivatives
作者:Jun-Dan Fang、Xiao-Biao Yan、Wu-Jie Lin、Yi-Chuan Zhao、Xue-Yuan Liu
DOI:10.1021/acs.orglett.9b02942
日期:2019.9.20
A diphenyl-diselenide-mediated Claisen-type rearrangement/cyclization of propargylic arylethers under metal-free conditions is developed, affording various naphthofuran-2-carboxaldehydes in moderate to excellent yield. The broad substrate scope and excellent functional group compatibility suggest that it can be a straightforward and powerful method to access naphthofuran-2-carboxaldehydes in a highly
Transient‐Ligand‐Enabled
<i>ortho</i>
‐Arylation of Five‐Membered Heterocycles: Facile Access to Mechanochromic Materials
作者:Bijin Li、Kapileswar Seth、Ben Niu、Lei Pan、Huiwen Yang、Haibo Ge
DOI:10.1002/anie.201713357
日期:2018.3.19
example of a direct arylation of heteroarenes by a transient‐ligand‐directed strategy without the need to construct and deconstruct the directing group. A wide range of heteroarenes undergoes the coupling with diverse aryl iodides to assemble a large library of highly selective and functionalized 3‐arylthiophene‐2‐carbaldehydes. This route provides an opportunity to rapidly access new mechanofluorochromic
Efficient and Connective Assembly of Highly Functionalized Benzofurans Using <i>o</i>-Hydroxyphenones and Dichloroethylene
作者:Florian Schevenels、István E. Markó
DOI:10.1021/ol300186s
日期:2012.3.2
The preparation of highly functionalized benzofurans by a unique and connective transformation is reported. Base-catalyzed condensation of o-hydroxyphenones with 1,1-dichloroethylene generates the corresponding chloromethylene furans. These labile intermediates undergo a facile rearrangement into benzofuran carbaldehydes under mild acidic conditions.
CHATTERJEA J. N.; BHAKTA C.; LAL S., INDIAN J. CHEM., 1978, B 16, NO 7 567-569