1.3- Diamines metal complexes

Cyclodextrins classification, 920 Cyclohexane-1,2-diamine metal complexes, 34 C.yclohexanc-l,2-dione monooxime metal complexes, 273 Cyclohexane-1,3,5-triamine metal complexes, 50 Cyclohexanone oxime... 

Fig. 12.29 The tel conformer of the A or o enantiomer of tris(diamine) metal complexes. The hatched circles represent the positions of the methyl groups in the propylene-diamine complex. For propylenediamine, this represents the ASSS or d6S5 isomer. [Modified from Corey, E. J. Bailar, J. C., Jr. J. Am. Chem. Soc.

The immobilization of metal catalysts onto sohd supports has become an important research area, as catalyst recovery, recycling as well as product separation is easier under heterogeneous conditions. In this respect, the iron complex of the Schiff base HPPn 15 (HPPn = iVA -bis(o-hydroxyacetophenone) propylene diamine) was supported onto cross-linked chloromethylated polystyrene beads. Interestingly, the supported catalyst showed higher catalytic activity than the free metal complex (Scheme 8) [50, 51]. In terms of chemical stability, particularly with... 

Sakaki S (2005) Theoretical Studies of C-H s-Bond Activation and Related by Transition-Metal Complexes. 12 31-78 Satoh T, see Miura M (2005) 14 1-20 Satoh T, see Miura M (2005) 14 55-84 Savoia D (2005) Progress in the Asymmetric Synthesis of 1,2-Diamines from Azomethine Compounds. 15 1-58 Schmalz HG, Gotov B, Bbttcher A (2004) Natural Product Synthesis. 7 157-180 Schmidt B, Hermanns J (2004) Olefin Metathesis Directed to Organic Synthesis Principles and Applications. 13 223-267... 

Recent studies on Ru catalysts bearing an arene and a secondary diamine or ethanolamine as ancillary ligands, in the presence of a base such as KOH as co-catalyst, seem, however, to contradict statement (a), suggesting a mechanism where substrate/metal complexation is not essential for alcohol —> C = X (X = O and N) hydrogen transfer to occur.30 115... 

Amines such as diethylamine, morpholine, pyridine, and /V, /V, /V, /V -tetramethylethylene-diamine are used to solubilize the metal salt and increase the pH of the reaction system so as to lower the oxidation potential of the phenol reactant. The polymerization does not proceed if one uses an amine that forms an insoluble metal complex. Some copper-amine catalysts are inactivated by hydrolysis via the water formed as a by-product of polymerization. The presence of a desiccant such as anhydrous magnesium sulfate or 4-A molecular sieve in the reaction mixture prevents this inactivation. Polymerization is terminated by sweeping the reaction system with nitrogen and the catalyst is inactivated and removed by using an aqueous chelating agent. 

The crystal structures of alkaline earth metal complexes of several (1 + 1) and (2 + 2) Schiff base macrocycles have been reported. These macrocycles are formed by the metal template-controlled condensation of the required heterocyclic dicarbonyl derivative and a, co functional diamine in alcoholic solution. (1 +1) complexes arise from the condensation reaction of one dicarbonyl with one diamine and (2 + 2) complexes from the condensation of two dicarbonyls with two diamines. 

When the metals exist in the complexed form, it is necessary to break up the complexes and transform the metals to "free" form amenable to chemical precipitation. Metal complexes consist of a central metal ion surrounded by a group of other organic or inorganic ions or molecules. Examples of complexing molecules are ammonia, citrates, and ethylene diamine tetra acetic acid (EDTA). 

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