1,3-Propanediamine cobalt complexes

D. ALKYL[2-[l-[(3-AMINOPROPYL)IMINO]ETHYL]-PHENOLATO](l,3-PROPANEDIAMINE)COBALT(ni) IODIDE (The Series of the [lb]I Complexes)... 

Cobalt, tris(l,2-propanediamine)-complexes structure, 1, 25 conformation, 1,25 nomenclature, 1, 129 stereonotation, 1,129... 

Using a quadridentate ligand derived from 1,3-propanediamine and 2,3-butanedione the cobalt-oxime complex (61) was prepared, and again in presence of the chiral base quinine (60) this was used to hydrogenate benzil according to equation (54) in an optical yield of 79%.277 These cobalt systems permitted only low turnover numbers to be achieved. 

The condensation of 2V,A -bis(3-aminopropyl)ethylenediamine (7V,A -ethylene-bis[l,3-propanediamine]) as its acid salt with 2,3-butanedione (biacetyl) in the presence of cobalt(II) or nickel(II) acetate gives complexes of 2,S-Mej [14] - 1,3-diene-l,4,8,11-N4 containing one a-diimine linkage. Experiments have shown that the presence of H ion determines whether or not a macrocyclic complex forms and that, in the presence of H, the time at which the metal acetate is added to the reaction mixture influences the yield of the complex. Unlike the reaction between biacetyl and 1,3-propanediamine to form 2,3,9,10-Me4[14]-1,3,8,10-tetraene-l,4,8,11-N4 (Sec. 4), the condensation of biacetyl withTVA -bis(3-aminopropyl)ethylenediamine is particularly sensitive to excess acetate so that the procedures given use the optimized conditions. 

The template condensation of a-diketones with 1,3-propanediamine in the presence of divalent iron, cobalt, nickel, or copper leads to 14-membered-ring macrocyclic complexes containing two a-diimines. A number of complexes of this class, derived from 2,3-butanedione,1-3 1-phenyl-1,2-propanedione,4,5 benzil,6 and substituted benzils,5 have been prepared. Preparation of the Ni(II)... 

The versatility of the Field-Durrant solution for the synthesis of cobalt(III) complexes depends largely upon high lability of tricarbonatocobaltate(III) in the substitutions, but kinetic studies concerning such labile nature are limited at present. However, pioneering papers by Davies and Hung studied the substitutions of tricarbonato-cobaltate(III) with pyridine ethylen liamine 1,2-prof ediamine (1,2-pn) and 1,3-propanediamine 1,3-pn) A solution prepared by dissolving Na3[Co(C03 J... 

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