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Cyclic closed ligand

In the series, cyclic closed ligands predominate, though there are occasional examples of open ligands (Scheme 14.12). The j cyclooctadiene FeCp" complex 29, for example, reacts with nucleophiles at the least-hindered end of the com-plexed triene [144]. [Pg.585]

Figure 1.16 Linear phosphopeptide 43 and cyclic phosphopeptide ligands 44 and 45 obtained by ring-closing metathesis showing virtually no difference in affinity for the Grb2 SH2 domain as measured by a surface plasmon resonance assay [61]. Figure 1.16 Linear phosphopeptide 43 and cyclic phosphopeptide ligands 44 and 45 obtained by ring-closing metathesis showing virtually no difference in affinity for the Grb2 SH2 domain as measured by a surface plasmon resonance assay [61].
Rule 2 Open ligands with interrupted conjugation react before closed ligands with cyclic conjugation. Rule 1 takes precedence over rule 2 if they conflict. [Pg.209]

Internal ligand-gated Open or close in response to a specific intracellular molecule, eg, a cyclic nucleotide. [Pg.568]

A polymeric structure can be generated by intermolecular coordination of a metalloporphyrin equipped with a suitable ligand. Fleischer (18,90) solved the crystal structure of a zinc porphyrin with one 4-pyridyl group attached at the meso position. In the solid state, a coordination polymer is formed (75, Fig. 30). The authors reported that the open polymer persists in solution, but the association constant of 3 x 104 M 1 is rather high, and it seems more likely, in the light of later work on closed macrocycles (see above), that this system forms a cyclic tetramer at 10-3 M concentrations in solution (71,73). [Pg.249]

Figure 3.55(a) shows a cyclic voltammogram of a Pt electrode immersed in a solution of the complex in acetonitrile. The peak labelled A was found to be insensitive to replacing the Cl by other ligands, an observation that was taken as strong evidence that the first reduction process is localised on the bipyridinc ligand. This was supported by the fact that the peak potential of the wave, —1.35 V vs. SCE, occurs relatively close to the first cathodic peak for (Bipy)3Ru2 +, — 1.29 V, which is known to involve the Bipy. [Pg.311]

The kinetics and mechanism of formation and dissociation of macrocyc-lic complexes is an area covering a wide range of behaviour. Indeed, the mechanistic details of a particular reaction are often closely associated with both the type of metal ion present and the structural features of the cyclic ligand. As such, there are often difficulties in defining general mechanisms which have wide applicability. In this discussion, some representative reactions are considered with emphasis on those features arising from the cyclic nature of the respective systems. [Pg.192]

We consider first the class structure of Sn. To do this, we note that every permutation may be written as the product of a number of independent cyclic permutations. Thus, the permutation s takes the ligand on site 1 to si, that on si to s(si), that on s(si) to s[s(si)], etc. Following this chain, since n is finite, we must eventually reach a site whose ligand is taken to site 1 by s. The closed chain evidently forms a cyclic permutation, which we will denote by writing the sites concerned in order enclosed in parentheses. Thus, (123.../) denotes a permutation s for which si =2, s2=3,. .. s/ i =/, s/= 1. If this first cycle does not include all the sites, we can do the same thing with the lowest-numbered site not appearing in the cycle, and continue until we have broken down the group element completely into a product of cycles.b>... [Pg.22]


See other pages where Cyclic closed ligand is mentioned: [Pg.617]    [Pg.617]    [Pg.153]    [Pg.173]    [Pg.301]    [Pg.213]    [Pg.30]    [Pg.274]    [Pg.37]    [Pg.171]    [Pg.327]    [Pg.572]    [Pg.14]    [Pg.63]    [Pg.67]    [Pg.391]    [Pg.256]    [Pg.263]    [Pg.327]    [Pg.625]    [Pg.67]    [Pg.225]    [Pg.12]    [Pg.38]    [Pg.196]    [Pg.201]    [Pg.209]    [Pg.206]    [Pg.4]    [Pg.526]    [Pg.854]    [Pg.97]    [Pg.15]    [Pg.773]    [Pg.397]    [Pg.192]    [Pg.185]    [Pg.362]    [Pg.87]    [Pg.134]    [Pg.64]    [Pg.62]    [Pg.114]   
See also in sourсe #XX -- [ Pg.585 ]




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