Deprotection, tethering, and activation of a catalytically active metalloporphyrin to a chemically active metal surface: [SAc](4)P-Mn(III)Cl on Ag(100).

نویسندگان

  • Mark Turner
  • Owain P H Vaughan
  • Georgios Kyriakou
  • David J Watson
  • Lukas J Scherer
  • Greg J E Davidson
  • Jeremy K M Sanders
  • Richard M Lambert
چکیده

The adsorption and subsequent thermal chemistry of the acetyl-protected manganese porphyrin, [SAc](4)P-Mn(III)Cl on Ag(100) have been studied by high resolution XPS and temperature-programmed desorption. The deprotection event, leading to formation of the covalently bound thioporphyrin, has been characterized and the conditions necessary for removal of the axial chlorine ligand have been determined, thus establishing a methodology for creating tethered activated species that could serve as catalytic sites for delicate oxidation reactions. Surface-mediated acetyl deprotection occurs at 298 K, at which temperature porphyrin diffusion is limited. At temperatures above approximately 425 K porphyrin desorption, diffusion and deprotection occur and at >470 K the axial chlorine is removed.

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عنوان ژورنال:
  • Journal of the American Chemical Society

دوره 131 5  شماره 

صفحات  -

تاریخ انتشار 2009