Tetraphenyloxybenziporphyrin, a New Organometallic Ligand for Silver(III) and Gold(III)

Abstract

[Structure: see text] Reaction of 4-hydroxyisophthalaldehyde with excess phenyl magnesium bromide gave a dicarbinol and this condensed with pyrrole and aromatic aldehydes in the presence of BF3.Et2O to afford, following oxidation with DDQ, novel tetraarylcarbaporphyrinoids in 10-24% yield. Further reaction with silver(I) acetate or gold(III) acetate gave stable organometallic derivatives that retained the aromatic characteristics of the parent macrocycle.

Metalation of Carbaporphyrinoid Systems

“…Ag III ) [41] and may find applications as catalysts. [59] In addition to discovering new organometallic systems, novel regioselective oxidation reactions have also been observed. [64] Oxidations of benzocarbaporphyrins with ferric chloride in the presence of alcohol solvents give carbaporphyrin ketals that have some promise as photosensitizers in PDT and are also being investigated as possible agents for treating leishmaniasis.…”

“…[21] However, this aromatic carbaporphyrinoid system can also be obtained by reacting the phenolic dicarbinol 49 with pyrrole and aromatic aldehydes under the LindseyRothemund conditions. [59] Although the meso-tetraaryl oxybenziporphyrins 50 show smaller upfield shifts than the meso-unsubstituted oxybenziporphyrins, the internal CH is still observed upfield near -3 ppm. [59] Benzocarbaporphyrins can also be derived from azuliporphyrins 6 (Scheme 4).…”

“…[59] Although the meso-tetraaryl oxybenziporphyrins 50 show smaller upfield shifts than the meso-unsubstituted oxybenziporphyrins, the internal CH is still observed upfield near -3 ppm. [59] Benzocarbaporphyrins can also be derived from azuliporphyrins 6 (Scheme 4). [38] Azuliporphyrins are relatively polar systems that derive borderline aromatic properties from dipolar canonical forms that simultaneously give the structure carbaporphyrin and tropylium aromatic characteristics.…”

“…Tetraphenyloxybenziporphyrins 50 have been shown to generate copper(III), silver(III) and gold(III) complexes 91, as well as a palladium(II) derivative. [59,60] Initial studies indicate that nickel(II) and platinum(II) complexes can be formed, but these have not been fully characterized. [60] Figure 6.…”

Late transition metal complexes of oxypyriporphyrin and the platinum(II) complex of oxybenziporphyrin

“…Oxybenziporphyrins can act as trianionic or dianionic ligands, readily affording silver(III) [10,23] and palladium(II) [24] complexes 5 and 6, respectively (Scheme 1). Related meso-tetraryl substituted oxybenziporphyrins also generate gold(III) complexes, a reaction that mostly results in decomposition for the meso-unsubstituted series [25]. Palladium(II) complex 6 was isolated as a potassium salt [24].…”