Organo-Polyoxometalate-Based Hydrogen-Bond Catalysis

Chemistry. 2021 Dec 20;27(71):17761-17764. doi: 10.1002/chem.202102807. Epub 2021 Nov 5.

Abstract

Several urea-inserted organo-polyoxometalates (POMs) derived from polyoxotungstovanadate [P2 V3 W15 O61 ]9- were prepared. The insertion of the carbonyl into the polyoxometallic framework activates the urea toward Hydrogen-bond catalysis. This was shown on the Friedel-Crafts arylation of trans-β-nitrostyrene. Modelling shows that the most stable form of the organo-POMs features a cis-trans arrangement of the two N-H bonds, but that the likely catalytically active trans-trans form is accessible at room temperature. Finally, it is possible that the oxo substituents next to the vanadium atoms may help the approach of the nucleophile via H-bonding.

Keywords: cooperative effects; hydrogen bonds; organic-inorganic hybrid composites; organocatalysis; polyoxometalates.

MeSH terms

  • Catalysis
  • Hydrogen
  • Hydrogen Bonding
  • Urea*
  • Vanadium*

Substances

  • Vanadium
  • Hydrogen
  • Urea