folder

A general one-pot synthesis of 2H-indazoles using an organophosphorus-silane system

Authors

  • J. Schoene
  • H. Bel Abed
  • P. Schmieder
  • M. Christmann
  • M. Nazaré

Journal

  • Chemistry - A European Journal

Citation

  • Chemistry 24 (36): 9090-9100

Abstract

  • A simple and direct approach for the regioselective construction of the privileged 2H‐indazole scaffold is described. The developed one‐pot strategy involves phospholene‐mediated N−N bond formation to access 2H‐indazoles. The amount of organophosphorus reagent was minimized by recycling the phospholene oxide with organosilane reductants. Starting from functionalized 2‐nitrobenzaldehydes and primary amines, a mild reductive cyclization, involving the use of commercially available phospholene oxide and silanes, delivered a wide variety of substituted 2H‐indazoles in good to excellent yields.


DOI

doi:10.1002/chem.201800763