Triribbed-functionalized clathrochelate iron(II) dioximates as a new and promising tool to obtain polynucleating and polynuclear compounds with improved properties
Yz. Voloshin et al., Triribbed-functionalized clathrochelate iron(II) dioximates as a new and promising tool to obtain polynucleating and polynuclear compounds with improved properties, INORG CHEM, 39(9), 2000, pp. 1907-1918
Template condensation on iron(II) ion of dichloroglyoxime (H(2)C12Gm) with
(C6H5O)(3), n-C4H9B(O-n-C4H9)(2), and BF3. O(C2H5)(2) in CH3NO2 afforded re
active clathrochelate precursors Fe(C12Gm)(3)(BC6H5); (2), Fe(C12Gm)(3)-(B-
n-C4H9)(2) (3), and Fe(C12Gm)(3)(BF)(2) (4). A series of triribbed-function
alized clathrochelate dioximates have been synthesized. Reaction of 2 with
C6H5SH/K2CO3 and CH3SH/t-C4H9OK in 1,4-dioxane and THF afforded Fe((C6P5S)2
Gm)(3)(BC6H5)(2) (5) and Fe((CH3S)2Gm)(3)(BC6H5)(2) (6). Reaction of 3 with
C6H5OK THF afforded Fe ((C6H5O)2Gm)(3)(B-n-C4H9)(2) (7). Condensation of 3
with bis(2(o-oxyphenoxy))diethyl ether in THF afforded di- and tricrown et
heric Fe(CwGm)(2)(C12Gm)(Bn-C4H9)(2) (8) and Fe(CwGm)(3)(B-n-C4H9)(2) (9) c
lathrochelates. Condensation of 3 with 3,5-dithiaoctane-1,8-dithiol/Cs2CO3
in DMF afforded the thiocrown etheric Fe((12anS(4))- Gm)(3)(BC6h5)(2) compl
ex (10). Reaction of 2 with n-butylamine in DMF resulted in the tetrasubsti
tuted Fe((n-C4H9NW)2Gm)(2)(C12Gm)(BC6H5)(2) clathrochelate (11). The clathr
ochelates obtained have been characterized both on the basis of elemental a
nalysis, FAB and PD mass spectrometry, IR, UV-vis, Fe-57 Mossbauer, and NMR
spectroscopies and crystallographically (compounds 3, 4, 6, 7, and ii). An
encapsulated iron(II) ion in a distorted trigonal-prismatic environment of
six nitrogen atoms of the macrobicyclic ligand was found to be in a low-sp
in state. The cyclic voltammograms for the complexes 2-11 show irreversible
oxidation waves assignable to Fe3+/Fe2+ couples. The con elation of E-1/2
for these couples with Hammet sigma(para) constants for substituents in dio
ximate fragments has been demonstrated.