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Halide anion mediated dimerization of a meso-unsubstituted N-confused porphyrin
Hiroyuki Furuta1,2, Hideki Nanami3, Tatsuki Morimoto1
1Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan, Fax: (+81) 92-802-2865.
Abstract:
The new N-confused porphyrin (NCP) derivatives, meso-unsubstituted beta-alkyl-3-oxo N-confused porphyrin (3-oxo-NCP) and related macrocycles, were synthesized from appropriate pyrrolic precursors by a [3+1]-type condensation reaction. 3-Oxo-NCP forms a self-assembled dimer in dichloromethane that is stabilized by complementary hydrogen-bonding interactions arising from the peripheral amide-like moieties. The protonated form of 3-oxo-NCP was observed to bind halide anions (F(-), Cl(-)) through the outer NH and the inner pyrrolic NH groups, thus affording a dimer in dichloromethane. The structure of the chloride-bridged dimer in the solid state was determined by X-ray diffraction analysis.
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