Synthesis of H-pyrazolo[5,1-a]isoquinolines via copper(II)-catalyzed oxidation of an aliphatic C-H bond of tertiary amine in air

Org Lett. 2011 Feb 18;13(4):712-5. doi: 10.1021/ol102939r. Epub 2011 Jan 6.

Abstract

A multicomponent reaction of 2-alkynylbenzaldehyde, sulfonohydrazide, and tertiary amine is discovered, which generates the unexpected H-pyrazolo[5,1-a]isoquinolines in good yields under mild conditions. In the reaction process, silver(I)-catalyzed intramolecular cyclization and copper(II)-catalyzed oxidation of an aliphatic C-H bond of tertiary amine in air are involved.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amines / chemistry*
  • Benzaldehydes / chemistry*
  • Catalysis
  • Copper / chemistry*
  • Cyclization
  • Heterocyclic Compounds, 3-Ring / chemical synthesis*
  • Heterocyclic Compounds, 3-Ring / chemistry
  • Isoquinolines / chemical synthesis*
  • Isoquinolines / chemistry
  • Molecular Structure
  • Oxidation-Reduction
  • Pyrazoles / chemical synthesis*
  • Pyrazoles / chemistry
  • Sulfonamides / chemistry*

Substances

  • Amines
  • Benzaldehydes
  • Heterocyclic Compounds, 3-Ring
  • Isoquinolines
  • Pyrazoles
  • Sulfonamides
  • Copper