Copper coordinate

Meerwein Arylation Reactions. Aryl diazonium ions can also be used to form certain types of carbon-carbon bonds. The copper-catalyzed reaction of diazonium ions with conjugated alkenes results in arylation of the alkene, known as the Meerwein arylation reaction.114 The reaction sequence is initiated by reduction of the diazonium ion by Cu(I). The aryl radical adds to the alkene to give a new (3-aryl radical. The final step is a ligand transfer that takes place in the copper coordination sphere. An alternative course is oxidation-deprotonation, which gives a styrene derivative. 

Fig. 17. Comparison of the copper coordination environments in [TpB"lCuCl and [TpBu Me]CUCl. Reprinted from Polyhedron, 14, Yoon, K., and Parkin, G., p. 811, copyright 1995, with kind permission from Elsevier Science Ltd, The Boulevard, Langford Lane, Kidlington 0X5 1GB, UK.

The ligand 2,5-bis(2-pyridyl)pyrazine was used in the synthesis of a range of zinc compounds to contrast with copper coordination polymers prepared with this ligand.169 Three zinc compounds were structurally characterized, [ZnCl2L(DMF)], [Zn3(OAc)6L2], and [Zn3Cl6L3] respectively a distorted square planar monomer, a linear trimer, and a triangular arrangement of zinc centers. 

Model systems for Type I copper proteins structures of copper coordination compounds with thioether and azole-containing ligands.17... 

Karlin KD, Zubieta J (1983) Copper coordination chemistry biochemical and inorganic perspectives. Adenine, New York... 

Figure 5.7 Schematic diagram of copper coordination in Panulirus He. (Adapted with permission from Figure 16 of Volbeda, A. Hoi, W. G. J. J. Mol. Biol., 1989, 209, 249-279. Copyright 1989, Academic Press.)...

A similar C, symmetric arrangement can be found for Cu[pz(iV-Me2)8] C60 (Fig. 32) (38). The distance from the centroid of the C60 molecule to the N4 coordination planes is found to be the same as 1121 p (/V-Mc2)>,I C60 (6.32 A). Interesting is the short distance of one of the carbons of C60, which is only 2.36 A above the copper coordination plane. The structure of Cu[pz(iV-Me2)8] C60 includes solvent molecules but it crystallizes in a 2D rather than a 3D network. The pattern of -pz-C60-pz-pz-C60-pz- and -C60l-sol vcn t-C60,-sol vcn I- sandwiches are retained, but in the third direction adjacent sheets are laterally displaced so that there is no linear -C60-Cgo-Cgo- sequence present. 

Figure 14.5 Copper-coordination sites in deoxy- and oxy-haemocyanin. (From Hatcher and Karlin, 2004. With kind permission of Springer Science and Business Media.)...

In agreement with the chemical reversibility of the Cu(II)/Cu(I) reduction, the reduced form of rusticyanin possesses a copper coordination quite similar to that of the oxidized form.69... 

Copper Coordination Chemistry Biochemical and Inorganic Perspectives, K lin, K. D. Zubieta, J., Eds. Adenine Press Guilderland, N.Y., 1983. 

Manoharan, P. T. Alston, K. Rifkind, J. M. Proc. Copper Coordination Conf. 1986, Albany, NY, in press. 

An electron-transfer protein containing a type-1 copper site that manifests itself by a strong visible absorption spectum. Another characteristic attributable to copper coordination by a cysteinyl sulfur is the EPR signal that displays an unusually small hyperline coupling to the copper nucleus. 

While only tyrosinase catalyzes the ortho-hydroxylation of phenol moieties, both tyrosinase and catechol oxidase mediate the subsequent oxidation of the resulting catechols to the corresponding quinones. Various mono- and dinu-clear copper coordination compounds have been investigated as biomimetic catalysts for catechol oxidation [21,194], in most cases using 3,5-di-tert-butylcatechol (DTBC) as the substrate (Eq. 16). The low redox potential of DTBC makes it easy to oxidize, and its bulky tert-butyl groups prevent un-... 

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