Iron complexes 1,4,8,11-tetraazacyclotetradecane

The characterization, redox properties, and pulse radiolysis study of manganese(III) complexes of type [MnLCy (where L = cyclam, meso-, and rac-5,7,7,12,14,14-hexamethylcyclam (tet a and tet b, respectively)) have been reported." An X-ray crystal structure of the meso-5,l,l, 2, A, A-hexamethyl-l,4,8,ll-tetraazacyclotetradecane complex shows that the coordination geometry of the tet a complex is close to octahedral with the macrocycle coordinated equatorially and the chlorides occupying irons axial sites. 

Busch and coworkers193) have also synthesized and characterized six-coordinate iron(II) complexes [Fe([14]aneN4)X2], where [14]aneN4 refers to the 14-membered fully saturated macrocyclic tetradentate ligand meso-5,5,7,12,12,14-hexamethyl-l,4,-8,11-tetraazacyclotetradecane. The complexes are found to be predominantly low-spin, when the axial ligands X are relatively strong examples, in spectrochemical order, are CN" > N02 > NCS" > CH3CN. 

The electropolymerization method of functional monomers has proved successful in many cases, in particular to incorporate various ligands and their metallic complexes, like salen [66,245], porphyrin [246], diphosphine [247], pyridine [71,80,248,249], crown ether [250,251], metallofullerene [252], tetraazacyclotetradecane [253], or Prussian blue type [254] in a conjugated organic material like PPy, PTh, or PANE Thick films are likely to be obtained provided that the polymer is redox active at the deposition potential due to this, Zotti et al. demonstrated that 5,5 -bis(3,4-(ethylenedioxy)thien-2-yl)-2,2 -bipyridine could be electropolymerized when complexed by iron and ruthenium, but not in the case of complexation by nickel or copper [71]. 

H-Spirophosphoranes Promising ligands in transition metal chemistry, an outlook of their coordination and catalytic properties 13CCR1039. Intrinsic properties and reactivities of mononuclear nonheme iron—oxygen complexes bearing the tetramethylcyclam (1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane) l%and 13CCR381. 

The basic reaction catalyzed by CODH is related to the water gas shift reaction employed industrially to generate H2 by the reaction of CO and H2O. Industrially the process is iron-catalyzed, and numerous organometallic complexes effect the same reaction [133]. Additionally, square-planar Ni(II) complexes electrocatalyze the reduction of CO2 to CO, including [Ni (cyclam)] (cyclam = 1,4,8,11-tetraazacyclotetradecane), nickel-porphyrins and phthalocyanines. The cluster [Fe4S4(SR)4] and certain Fe-porphyrins also catalyze this reaction [124]. 

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