Alkynoxy-Directed C–H Functionalizations: Palladium(0)-Catalyzed Annulations of Alkynyl Aryl Ethers with Alkynes

• Minami Yasunori

  Research and Development Initiative, Chuo University JST, ACT-C

• Shiraishi Yuki

  Department of Applied Chemistry, Chuo University

• Kodama Tatsuro

  Department of Applied Chemistry, Chuo University

• Kanda Mayuko

  Department of Applied Chemistry, Chuo University

• Yamada Kotomi

  Department of Applied Chemistry, Chuo University

• Anami Tomohiro

  Department of Applied Chemistry, Chuo University

• Hiyama Tamejiro

  Research and Development Initiative, Chuo University JST, ACT-C

Bibliographic Information

Other Title

• Selected Paper : Alkynoxy-Directed C-H Functionalizations : Palladium(0)-Catalyzed Annulations of Alkynyl Aryl Ethers with Alkynes

Abstract

Palladium(0)-catalyzed insertion/annulation sequence between aryl silylethynyl ethers and internal alkynes was found to proceed through activation of ortho-C–H bonds assisted by alkynoxy groups and gave stereoselectively (Z)-2-silylmethylenechromenes. These products could be easily converted into 2,2-alkylated 2H-chromene derivatives, an important structural motif in medicinal chemistry and materials science. Various aryl silylethynyl ethers and alkynes can be transformed under the reaction conditions, and a wide range of chromenes is thus accessible. When unsymmetric alkynes are employed, a regioselective annulation takes place, especially those containing aryl and/or bulky substituents. Catalytic systems based on palladium(0), such as Pd(OAc)₂/PCy₃/Zn, [Pd(dba)₂]/PCy₃, or Pd(PCy₃)₂ exhibit excellent catalytic activity, and the best performance is observed for Pd(PCy₃)₂ in combination with Zn(OAc)₂ as an additive. Substituents on the aryl group in the alkynyl aryl ethers rarely affect the reaction rate. Deuterium-labeling experiments suggest that the ortho-hydrogen atom migrates to the 2-methylene position in the chromene products. The cleavage of the C–H bond is considered to be the rate-determining step in these reactions.

Journal

• Bulletin of the Chemical Society of Japan

  Bulletin of the Chemical Society of Japan 88 (10), 1388-1403, 2015

  The Chemical Society of Japan

Keywords

• General Chemistry

Details

• CRID: 1390001204141347840
• NII Article ID: 130005102809
• NII Book ID: AA00580132
• DOI: 10.1246/bcsj.20150180
• ISSN: 13480634
• ISSN: 00092673
• NDL BIB ID: 026791162
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I026791162
• Web Site: https://academic.oup.com/bcsj/article-pdf/88/10/1388/56278324/bcsj.20150180.pdf
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed