[4 + 2] Cyclocondensation reactions of tungsten-dihydropyridine complexes and the generation of tri- and tetrasubstituted piperidines

J Am Chem Soc. 2011 Nov 16;133(45):18378-87. doi: 10.1021/ja2075086. Epub 2011 Oct 26.

Abstract

A new method for the preparation of functionalized piperidines is described in which various dihydropyridine (DHP) complexes of {TpW(NO)(PMe(3))} that are derived from pyridine-borane undergo [4 + 2] cyclocondensation with enones, enals, nitrosobenzene, and several isocyanates to form [2.2.2] bicyclic species. In several cases the diazabicyclooctene products derived from DHP complexes and isocyanates can be further elaborated into novel syn-2,5-disubstituted and 2,3,6-trisubstituted piperidinamides.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cyclization
  • Dihydropyridines / chemistry*
  • Molecular Structure
  • Organometallic Compounds / chemical synthesis*
  • Organometallic Compounds / chemistry
  • Piperidines / chemical synthesis*
  • Piperidines / chemistry
  • Stereoisomerism
  • Tungsten / chemistry*

Substances

  • Dihydropyridines
  • Organometallic Compounds
  • Piperidines
  • 1,4-dihydropyridine
  • Tungsten