SYNTHESIS AND CHARACTERIZATION OF GALLIUM(III) 2-HYDROXY-5,10,15,20-TETRAPHENYLPORPHYRIN - A NOVEL EXAMPLE OF A CYCLIC GALLIUM(III) PORPHYRIN TRIMER

被引:38
作者
WOJACZYNSKI, J [1 ]
LATOSGRAZYNSKI, L [1 ]
机构
[1] UNIV WROCLAW, INST CHEM, PL-50383 WROCLAW, POLAND
关键词
D O I
10.1021/ic00109a010
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
A trimeric [(2-O-TPP)Ga-III](3) complex (2-O-TPP is a trianion of 2-hydroxy-5,10,15,20-tetraphenylporphyrin) was obtained by hydrolysis of the monomeric five-coordinate complex (2-BzO-TPP)(GaCl)-Cl-III (2-BzO-TPP is a dianion of 2-benzoyloxy-5,10,15,20-tetraphenylporphrin) with sodium hydroxide in ethanol. The H-1 NMR spectra of the trimer and its monomeric precursors: (2-BzO-TPP)(GaCl)-Cl-III, (2-OH-TPP)Ga(III)TFA are presented and analyzed. The spectroscopic evidences indicated that the trimeric gallium(III) complex has a head-to-tail cyclic trimeric structure with the pyrrolic-alkoxide groups forming bridges from one macrocycle to the metal in the adjacent macrocycle PGa-O-PGa-O-PGa-O. The three gallium(III) porphyrin subunits are not equivalent. Their spatial proximity produces a marked variation of the chemical shifts due to a contribution of the ring current effect. The unprecedented positions of the 3-H pyrrole resonances (1.82, 2.18, 2.82 ppm), when compared to (2-BzO-TPP)(GaCl)-Cl-III (8.96 ppm), reflect the coordination of 2-0 centers to the adjacent gallium(III) ions. The strong effects were also determined for ortho 20-phenyl resonances ([(2-O-TPP)Ga-III](3), 5.21, 5.36, 5.69, 5.78, 5.93, and 6.33 ppm; (2-BzO-TPP)(GaCl)-Cl-III, 7.9-8.4 ppm). A two-dimensional COSY experiment was effective in connecting the protons within the phenyl and pyrrole rings. The complete peak assignments were derived from the NOESY experiment. In particular, closed loops of the NOE connectivities, which involved interporphyrin contacts between all subunits of the trimer, were analyzed and provided unambiguous spectroscopic evidence for the cyclic trimer formation. The trimer was cleaved in the reversible process to the monomeric complexes: (2-OH-TPP)(GaCl)-Cl-III and [(2-O-TPP)Ga-III(OH)](-) by addition of HCl or OH-, respectively. The formation of the expanded linear intermediate was demonstrated in the course of the acidic cleavage. The differences of pyrrole chemical shifts demonstrated for the gallium(III) monomeric species and the increased lability of the 3-H pyrrole proton resulted from the tautomeric phenol-enol-ketone equilibria typical for the 2-OH-TPPH2 porphyrin.
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页码:1054 / 1062
页数:9
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共 72 条
[1]   NMR-SPECTRA OF PORPHYRINS .13. RING CURRENT MODEL FOR PORPHYRIN AND CHLORIN (7,8-DIHYDROPORPHYRIN) RINGS [J].
ABRAHAM, RJ ;
FELL, SCM ;
SMITH, KM .
ORGANIC MAGNETIC RESONANCE, 1977, 9 (06) :367-373
[2]   THE NMR-SPECTRA OF THE PORPHYRINS .16. ZINC(II) MESO-TETRAPHENYLPORPHYRIN (ZN TPP) AS A DIAMAGNETIC SHIFT-REAGENT - A QUANTITATIVE RING CURRENT MODEL [J].
ABRAHAM, RJ ;
BEDFORD, GR ;
MCNEILLIE, D ;
WRIGHT, B .
ORGANIC MAGNETIC RESONANCE, 1980, 14 (05) :418-425
[3]   RECOGNITION OF GIANT CLUSTER ANIONS BY A PROTONATED PORPHYRIN TRIMER - DETECTION BY FAST-ATOM-BOMBARDMENT (FAB) MASS-SPECTROMETRY [J].
ANDERSON, HL ;
SANDERS, JKM .
JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1992, (13) :946-947
[4]   AMINE-TEMPLATE-DIRECTED SYNTHESIS OF CYCLIC PORPHYRIN OLIGOMERS [J].
ANDERSON, HL ;
SANDERS, JKM .
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1990, 29 (12) :1400-1403
[5]   SCAVENGER TEMPLATES - SYNTHESIS AND ELECTROSPRAY MASS-SPECTROMETRY OF A LINEAR PORPHYRIN OCTAMER [J].
ANDERSON, S ;
ANDERSON, HL ;
SANDERS, JKM .
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH, 1992, 31 (07) :907-910
[6]   SYNTHESIS OF COVALENTLY LINKED PORPHYRIN DIMERS AND TRIMERS [J].
ANTON, JA ;
KWONG, J ;
LOACH, PA .
JOURNAL OF HETEROCYCLIC CHEMISTRY, 1976, 13 (04) :717-725
[7]   AXIAL ALKYL LIGAND REACTIVITY IN 5-COORDINATE GALLIUM(III) PORPHYRIN COMPLEXES [J].
BALCH, AL ;
HART, RL ;
PARKIN, S .
INORGANICA CHIMICA ACTA, 1993, 205 (02) :137-143
[8]   A COFACIAL, DIMERIC, METALLAOXOPHLORIN COMPLEX - [INDIUM(III)(OCTAETHYLOXOPHLORIN)](2) [J].
BALCH, AL ;
NOLL, BC ;
OLMSTEAD, MM ;
REID, SM .
JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1993, (13) :1088-1090
[9]   CHEMISTRY OF IRON OXOPHLORINS .1. H-1-NMR AND STRUCTURAL STUDIES OF 5-COORDINATE IRON(III) COMPLEXES [J].
BALCH, AL ;
LATOSGRAZYNSKI, L ;
NOLL, BC ;
OLMSTEAD, MM ;
ZOVINKA, EP .
INORGANIC CHEMISTRY, 1992, 31 (11) :2248-2255
[10]   COORDINATION PATTERNS FOR OXOPHLORIN LIGANDS - PYRIDINE-INDUCED CLEAVAGE OF DIMERIC MANGANESE(III) AND IRON(III) OCTAETHYLOXOPHLORIN COMPLEXES [J].
BALCH, AL ;
NOLL, BC ;
REID, SM ;
ZOVINKA, EP .
INORGANIC CHEMISTRY, 1993, 32 (12) :2610-2611