Nitrate single-ligand complexes

FABMS has been used as a semiquantitative indication of the selectivity of receptors for particular guest metal cations (Johnstone and Rose, 1983). The FABMS competition experiment on [7] with equimolar amounts of the nitrates of sodium, potassium, rubidium and caesium gave gas-phase complex ions of ([7] + K)+ ion (m/z 809) and a minor peak ([7] + Rb)+ ion (m/z 855) exclusively. The relative peak intensities therefore suggested a selectivity order of K+ Rb+ Na+, Cs+, indicative of the bis-crown effect, the ability of bis-crown ether ligands to complex a metal cation of size larger than the cavity of a single crown ether unit, forming a sandwich structure. 

In the case of complexes of lanthanide nitrates with CP (239), the infrared spectra exhibit two uCz=Q vibrations apart from a single pP=0- The J>p=o and one of the c=o vibrations occur at frequencies lower than the corresponding ligand frequencies But the second r>c=0 1S not much shifted from the free ligand value. These observations have been interpreted in terms of Structure VIII containing both coordinated... 

The first step of the mechanism leading The electrochemical study of the seven-to the formation of 8 and free nitrite coordinate complex [Mo(N2RR )(dtc)3]+ from the reaction of 7 with O2 probably 9+ (R, R = alkyl or aryl, dtc = 5 2CNMe2) involved a single electron transfer. Sub- provided an example of electrode-induced sequent radical-radical coupling of the activation of a hydrazido(2—) ligand. Corn-products, to afford a molybdenum-bound plex 9+ was shown to reduce in two nitrate, followed by N—O bond cleavage separate diffusion-controlled one-electron would eventually lead to the observed steps, with the first one reversible on the products (Sch. 8) [27]. CV timescale at room temperature and... 

Figure 10.1.1 Single Crystal X-Ray Diffraction Structure of Complex 10.1 (Bis-nitrate Form) Showing the Planar Nature of the Basic Monoanionic Texaphyrin Ligand and the Four Putative Inner Sphere Coordination Sites for Water (Occupied by Two Apical Methanol Molecules and a Bidentate Nitrate Anion in this Structure).

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