Structural and magnetic characterization of the chromium(III) dimers di-.mu.-hydroxo-bis[(4-hydroxo-2,6-dicarboxylatopyridine)aquachromium(III)] tetrahydrate, [Cr(chel)(OH2)OH]2.4H2O, and di-.mu.-hydroxo-bis[(4-chloro-2,6-dicarboxylatopyridine)aquachromium(III)] dihydrate, [Cr(Cl-dipic)(OH2)OH]2.2H2O

Diaquachlorido(4-hydroxypyridine-2,6-carboxylato-κ3N,O,O′)iron(III) 18-crown-6 dihydrate

“…For the crystal structure of [Fe(HChel)Cl(H 2 O) 2 ], see: Laine et al (1995). For other literature related to the use of chelidamic acid as a ligand, see: Cline et al (1979); Hall et al (2000); Ng (1998Ng ( , 1999; Riegel (1926); Thich et al (1976); Yang et al (2002).…”

The sodium salt of a tris(tridentate anion)gadolinium(III) complex: pentasodium bis[chelidamato(3−)][chelidamato(2−)]gadolinate(III) hexadecahydrate

“…For consideration and comparison of the metal-atom environment in the context of related species, the parameters of the present array may be compared with those of the dipicolinate counterpart complex ion as found in [Co(NH 3 ) 6 ][Gd(dipic) 3 ]Á11H 2 O (Table 2; Brayshaw et al, 2000), but with credibility enhanced by their close similarity to those of the Ln = Eu counterpart arrays (wherein the metal radius should differ by only ca 0.01 A Ê ), as recorded recently (Brayshaw et al, 1995). Ligand parameters may also be compared with those for other chelidamate species previously structurally characterized in [(chelH)M(OH)(OH 2 )] 2 Á4H 2 O (M = Fe, Cr), in which the metal ions are progressively much smaller species (M = Fe: Thich et al, 1976; M = Cr: Cline et al, 1979), and in various macrocyclic ether esters and associated derivatives (Nakatsuji et al, 1985;. Comparison of the [GdL 3 ] nÀ (L = dipic and chelH x ) data of Table 2 shows that, although the two complex species in general are quite similar, the incorporation of the aryloxide in the ring para to the metal atom is not totally without consequence for the geometry about the metal as well as within the ring.…”

“…With values of 1.329 (9), 1.334 (9) and 1.30 1 , 1985) show that the distance is 1.29 A Ê in the anionic form and 1.34 A Ê in the protonated form. However, in these latter and related species (Thich et al, 1976;Cline et al, 1979;, the angular parameters of the ring C atoms are usefully diagnostic of protonation or otherwise at the oxygen, the intraring angle being more greatly diminished (to 113.7 in this case) from 120 in the deprotonated form with symmetrical exocyclic angles, while in the protonated form the Unit-cell contents with 30% amplitude displacement ellipsoids projected down c. The quasi-32 symmetry of the anions is clearly seen.…”

Triaqua(4-hydroxypyridine-2,6-dicarboxylato-κ3N,O,O′)zinc(II)–acetonitrile–water(1/0.25/1)

“…It is also important in biochemistry, organic chemistry, and medical chemistry, even in HIV investigations (Berl et al, 2001;Ng, 1999;Nakatsuji et al, 1985;Boger et al, 1999;Fessmann & Kilburn, 1999;Bridger et al, 1999;Searcey et al, 1998). Metal complexes containing the chelidamate ligand have been reported for Fe III , Cr III , Sn IV , Gd III and V V (Ng, 1998(Ng, , 1999Riegel, 1926;Hall et al, 2000;Cline et al, 1979;Yang et al, 2002;Thich et al, 1976). Here we report the synthesis and crystal structure of a new Zn II compound, (I), with a chelidamate ligand.…”