Non-bridging

It has a VF4 type puckered sheet structure with 6-coordinated ruthenium four fluorines bridge, two non-bridging ones are trans with the terminal distances shorter as expected (Table 1.1). It is paramagnetic (/xeff = 3.04/xB at room temperature). 

Reaction of Rh2(OCOR)4 with dimethylglyoxime leads to a non-bridged dimer [81]. 

Figure 2.41 A dimeric non-bridged rhodium dimethylglyoxime complex (for clarity the hydrogen atoms in the hydrogen bonds are not shown).

Non-bridging ligands in electron transfer reactions. J. E. Earley, Prog. Inorg. Chem., 1970, 13, 243-262 (76). 

The role of oxygen in these inorganic polymers in important. In Zacheriasen s theory, oxygen was described as bridging if part of a covalent structure (10.4). When there was an ionic bond, the oxygen was described as non-bridging (10.5). 

AnsueP This diketo-ester has five sites for enolisation ( in 30a). Attack of these enols on the other carbonyl groups could produce ring sizes from ihree to nine but only one stable non-bridged cyclic... 

With a view to determining the equilibrium constant for the isomerisation, the rates of reduction of an equilibrium mixture of cis- and rra/i5-Co(NH3)4(OH2)N3 with Fe have been measured by Haim S . At Fe concentrations above 1.5 X 10 M the reaction with Fe is too rapid for equilibrium to be established between cis and trans isomers, and two rates are observed. For Fe concentrations below 1 X lO M, however, equilibrium between cis and trans forms is maintained and only one rate is observed. Detailed analysis of the rate data yields the individual rate coefficients for the reduction of the trans and cis isomers by Fe (24 l.mole sec and 0.355 l.mole .sec ) as well as the rate coefficient and equilibrium constant for the cw to trans isomerisation (1.42 x 10 sec and 0.22, respectively). All these results apply at perchlorate concentrations of 0.50 M and at 25 °C. Rate coefficients for the reduction of various azidoammine-cobalt(lll) complexes are collected in Table 12. Haim discusses the implications of these results on the basis that all these systems make use of azide bridges. The effect of substitution in Co(III) by a non-bridging ligand is remarkable in terms of reactivity towards Fe . The order of reactivity, trans-Co(NH3)4(OH2)N3 + > rra/is-Co(NH3)4(N3)2" > Co(NH3)sN3 +, is at va-... 

Figure 14-7. Snapshots of the active site structures near the transition state of (top) the nucleophilic attack and (bottom) the exocyclic cleavage for the in-line monoanionic O2p mechanism of cleavage transesterification in the hairpin ribozyme. The yellow and red colored cartoon is for the substrate and ribozyme strands, respectively, and water molecules interacting with non-bridging oxygens and O5/ are shown...

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