Synthesis of indaphyrins: meso-tetraarylsecochlorin-based porphyrinoids containing direct o-phenyl-to-beta-linkages

Org Biomol Chem. 2004 May 21;2(10):1484-91. doi: 10.1039/b401629g. Epub 2004 Apr 21.

Abstract

The synthesis of indaphyrins, novel meso-tetraarylsecochlorin-derived chromophores incorporating o-phenyl-to-beta-linkages, is described. Oxidative diol cleavage of meso-tetraaryl-2,3-dihydroxy-2,3-chlorins results in the formation of a secochlorin bisaldehyde. Depending on the reaction conditions during the ring cleavage reaction, one or two of the aldehyde groups react with the adjacent o-phenyl positions, leading to an intramolecular electrophilic aromatic substitution of the o-phenyl proton, and the establishment of a direct o-phenyl-to-beta-linkage. The initially formed carbinol is spontaneously oxidized to the corresponding ketone. This modification forces the aryl groups into co-planarity with the macrocycle, allowing for interactions between the pi-electrons of the aryl groups, the ketone linkage, and those of the chromophore, resulting in a significant electronic modulation of the porphyrinic pi-system. The UV-vis spectroscopic properties of the free base, CuII, NiII, and ZnII indaphyrins are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Computer Simulation
  • Copper / chemistry
  • Cyclization
  • Heterocyclic Compounds, 4 or More Rings / chemical synthesis*
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Structure
  • Nickel / chemistry
  • Porphyrins / chemistry*
  • Spectrophotometry, Ultraviolet
  • Thermodynamics
  • Zinc / chemistry

Substances

  • Heterocyclic Compounds, 4 or More Rings
  • Porphyrins
  • tetraphenylporphyrin
  • Copper
  • Nickel
  • Zinc