Fine tuning reactivity: synthesis and isolation of 1,2,3,12b-tetrahydroimidazo[1,2-f]phenanthridines

J Org Chem. 2009 Nov 6;74(21):8196-202. doi: 10.1021/jo901622e.

Abstract

A facile route for the synthesis and isolation of 1,2,3,12b-tetrahydroimidazo[1,2-f]phenanthridines (TIPs) has been developed. The heterocycle is a reactive intermediate in the three-step cascade synthesis of 2,3-dihydro-1H-imidazo[1,2-f]phenanthridinium cations (DIPs), a biologically active DNA intercalating framework; however, the intermediate has previously only been characterized in situ. Derivatization of the structure at the imidazo-N position controls the reactivity of the intermediate with respect to electronic potential and pK(a) allowing isolation of a selection of TIP structures. Correlations between these parameters and reaction outcome have been made, and other influences such as steric and solvent effects have also been investigated.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Crystallography, X-Ray
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Phenanthridines / chemical synthesis*
  • Phenanthridines / isolation & purification
  • Spectrophotometry, Infrared

Substances

  • Phenanthridines