A Practical, One-Pot Synthesis of Highly Substituted Thiophenes and Benzo[<i>b</i>]thiophenes from Bromoenynes and <i>o</i>-Alkynylbromobenzenes
作者:Verónica Guilarte、Manuel A. Fernández-Rodríguez、Patricia García-García、Elsa Hernando、Roberto Sanz
DOI:10.1021/ol201970m
日期:2011.10.7
An efficient synthesis of thiophenes and benzo[b]thiophenes has been developed from easily available bromoenynes and o-alkynylbromobenzene derivatives. This novel one-pot procedure involves a Pd-catalyzed C–S bond formation using a hydrogen sulfide surrogate followed by a heterocyclization reaction. Moreover, in situ functionalization with selected electrophiles further expands the potential of this
由容易获得的溴代炔和邻炔基溴苯衍生物已开发出噻吩和苯并[ b ]噻吩的有效合成方法。这种新颖的一锅法涉及使用硫化氢替代物进行钯催化的C–S键形成,然后进行杂环化反应。此外,用选定的亲电试剂进行原位官能化进一步扩大了该方法在制备相应的高度取代的硫杂环化合物方面的潜力。
Palladium-Catalyzed Dienylation of Haloalkynes using 2,3-Butadienyl Acetates: A Facile Access to (1Z)-1,2-Dihalo- 3-vinyl-1,3-dienes
A highly efficient and stereoselective method for the synthesis of (1Z)‐1,2‐dihalo‐3‐vinyl‐1,3‐dienes featuring palladium‐catalyzed coupling of haloalkynes and 2,3‐butadienyl acetates was developed. The resulting products were smoothly converted into cis‐1,2‐dihalostyrene derivatives using the Diels–Alder/aromatization sequence.
Pd-catalyzed coupling of haloalkynes with allyl acetate has been reported, providing a convenient method for the stereoselective synthesis of (Z)-β-haloenol acetates in good yields. The synthetic utility of this method is demonstrated by the formation of functionalized enol acetates via the Suzuki–Miyaura or Sonogashira coupling of the resulting (Z)-β-haloenol acetate products.
Hydrogen Bonding Cluster-Enabled Addition of Sulfonic Acids to Haloalkynes: Access to Both (<i>E</i>)- and (<i>Z</i>)-Alkenyl Sulfonates
作者:Xiaojun Zeng、Shiwen Liu、Zhenyu Shi、Bo Xu
DOI:10.1021/acs.orglett.6b02061
日期:2016.10.7
We developed an efficient synthesis of alkenyl sulfonates via hydrogen bonding cluster-enabled addition of sulfonic acids to haloalkynes. The reactivity of sulfonic acids could be significantly enhanced in the presence of strong hydrogen bonding donors. This metal-free method results in good chemical yields for a wide range of haloalkyne substrates and demonstrates good functional group tolerance.
Gold-Catalyzed Regio- and Stereoselective α-Acyloxy-β-Alkynylation of Ynol Ethers
作者:Yaowen Liu、Chunyu Han、Hongwei Shi、Alexandra V. Mackenroth、Linghua Zhang、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1021/acs.joc.2c02597
日期:2023.3.3
sciences. Herein, the synthesis of tetra-substituted enol ester 2-iodobenzoate derivatives was achieved in good yields at room temperature through a gold-catalyzed acyloxyalkynylation of sensitive ynol ethers with ethynylbenziodoxolones (EBXs), the latter acting as bifunctional reactants. The conversion is highly regioselective with a broad substrate scope. Mechanistically, an Au(III) species is the key