Copper TMED

The basic study was performed on copper complexes with N,N,N, N1-tetramethylethane-1,2-diamine (TMED), which were known to be very effective oxidative coupling catalysts (7,12). From our first kinetic studies it appeared that binuclear copper complexes are the active species as in some copper-containing enzymes. By applying the very strongly chelating TMED we were able to isolate crystals of the catalyst and to determine its structure by X-ray diffraction (13). Figure 1 shows this structure for the TMED complex of basic copper chloride Cu(0H)Cl prepared from CuCl by oxidation in moist pyridine. 

Figure 3. Effect of mineral base (NaOH) on the catalytic activity and specificity of the copper(II)-TMED complex. [CuCl2] = 3.33mM [DMP]0 = 0.06 M temp 25°C solvent 1,2-dichlorobenzene/methanol (9 1, v/v). The fraction DPQ was determined spectroscopically at 420 nm after 35% conversion.

The most useful approaches to the synthesis of di- and poly-ynes from terminal alkynes are undoubtedly the copper-catalyzed couplings discovered by Glaser (CuCl, NH4OH, EtOH, 02)," Eglinton [Cu(OAc)2, hot pyridine or quinoline, 02], and Hay [Cu(I), tmed, 02]. Some of the many applications of these reactions are discussed in the following. 

Alkane nitronates such as Zr(02N—CR2)4 are known. In Ni(02N=CHPh)2(tmed) the ligand is chelate through both oxygen atoms as it is apparently also in Ru(02N=CH2)H(PPh3)3 and some copper compounds such as [Cu(phen)02N=CH2]+. Some tin, lead, and mercury compounds have unidentate groups M0N(0)CR R". However, C bonding, as M—CH2NO2, is also possible, as in the platinum compounds made by the reaction... 

The kinetics and mechanism of the oxidative coupling polymerization of 2,6-DMP catalyzed by a copper(II)-tmed complex (tmed =... 

The complex ion [CuCHHIB) ] -, formed by the reaction of copper(ii) ions with hexafluorohydroxyisobutyric acid, is thought from its magnetic moment to have square-planar co-ordination. In the presence of ethylene-diamine (en) or tetramethylethylenediamine (tmed), amine salts [HaB] +[Cu(HHIB)2l (B = en or tmed) are formed a further product with ethylenediamine contains two diamine molecules per metal atom, and is thought to be the carboxylate complex H0-C(CF3)2 C02Cu(en)2 02C-QCF2)2(0H). ... 

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