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1,2-HOIQO--a highly versatile 1,2-HOPO analogue.

ABSTRACT: A cyclic, bidentate hydroxamic acid binding unit based on an isoquinoline scaffold has been utilized for the synthesis of a hexadentate tripodal ligand based on the TREN backbone. This prototype for a new class of multidentate chelators forms mononuclear iron(III) complexes and one-dimensional coordination polymers with lanthanide(III) cations. The latter has been determined by single-crystal X-ray analysis of the cerium species. The solid-state structure in the monoclinic space group P2(1)/c (C(36)H(34)CeN(7)O(11), a = 12.341(2) A, b = 26.649(4) A, c = 10.621(2) A, alpha = gamma = 90 degrees, beta = 96.753(3) degrees, V = 3468.6(9) A3, Z = 4) exhibits a trigonal-dodecahedral environment around the cerium cation. The proof of concept for the versatility of the new scaffold has been shown by the modification of the crucial precursor 3-carboxyisocoumarin through electrophilic aromatic substitutions to yield the corresponding chlorosulfonated and nitrated analogues.

SUBMITTER: Seitz M

PROVIDER: S-EPMC3190976 | biostudies-literature | 2007 Jan

REPOSITORIES: biostudies-literature

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1,2-HOIQO--a highly versatile 1,2-HOPO analogue.

Seitz Michael M Pluth Michael D MD Raymond Kenneth N KN

Inorganic chemistry 20070101 2

A cyclic, bidentate hydroxamic acid binding unit based on an isoquinoline scaffold has been utilized for the synthesis of a hexadentate tripodal ligand based on the TREN backbone. This prototype for a new class of multidentate chelators forms mononuclear iron(III) complexes and one-dimensional coordination polymers with lanthanide(III) cations. The latter has been determined by single-crystal X-ray analysis of the cerium species. The solid-state structure in the monoclinic space group P2(1)/c (C ...[more]

PMID: 17279805

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