O-Metallation

A new structure type with B atoms in O), metal coordination is found within the Rh-B system the structure of Rh5B4 is characterized by a (chhhc)2 stacking (BABABCACAC) of 10 closely packed Rh layers. In this case all holes between the layers are fully occupied by isolated B atoms, arranged in linear B4 groups (B—B -222 pm). 

Similar SSIMS and TDS results were obtained for rhodium on tltanla and fiir hydrogen chemisorption on both substrates. In a blank experiment Involving i o metal over layer, temperature programming while following the T1 and TIO SIMS signals (Fig. 4) shows that the tltanla thin film does not begin to change until the temperature reaches about 760 K, well beyond the 615 K where Tl was first noted to Increase on the systems with thin metal overlayers. ... 

Mine (%o) Metals produced Mine (%o) Metals produced... 

Larese, C., Lopez Granados, M., Mariscal, R. et al. (2005) The effect of calcination temperature on the oxygen storage and release properties of Ce02 and Ce—Zr—O metal oxides modified by phosphorus incorporation, Appl. Catal. B Environ., 59, 13. 

N O Metal METAL FULMINATES or acz-NITRO SALTS, OXIMATES... 

Unhke silanol groups, acidic P-OH groups cannot self-condense in solution, which discards the formation of P-O-P bonding. The formation of frameworks including phosphorus groups involves P-O-Metal hnkages (as in... 

A number of groups have been found to direct and stabilize o-metallation in aromatic systems since Meyers ( ) introduced the oxazolidine group for this purpose. It was reasoned that the imidazolinone group should also serve this purpose. It was gratifying to find that treatment of the pyridyl imidazolinone 22 th 2.2 equivalents of butyl lithium followed by carbon dioxide gave a good yield of the nicotinic acid 14 (R=H). 

Lithiation of the sterically hindered amide 395 leads to an equilibrium mixture of a-and o-metallated species, as shown in equation 107. This can be demonstrated by the usual methods of analysis of the products 396 and 397, obtained after quenching with an electrophile. The relative amounts of these products depend on the electrophile and mode of operation for example, the ratio is larger than 10 1 in favor of 397 for E = MesSi, whereas for E = Me it is 2 1 in favor of 396, which increases to 10 1 when addition of Mel... 

Fig. 2 Effects of metal salts, ligands, and initiators on Cmma (s)> / (b), PDls (c) of the polymers in the atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) in p-xylene at 90°C. [MMA]o [initiator]o [metal salt]o [ligand]o = 150 1 1 2, MMA/p —xylene = l 2v/v. EBIB, MBP, BEB, and TsCl were used as initiator from right to left in each ligand column, respectively (Reprinted with permission from [34]. Copyright (2004) John Wiley Sons, Inc.)...

Speromagnetism (Fig. 6.5 d) is a property of some amorphous or poorly ordered materials containing metal-O-metal bonds which, if the metal carries a magnetic moment, can support super-exchange reactions (Coey Readman, 1973). 

Directed ort o-metalations are also applied to quinoxalines possessing 2-chloro, 2-methoxy, and pivaloylamino substituents <1993JHC1491>, but successful syntheses via the lithio intermediates are far fewer compared to pyrazines. In fact, no example of metalation on aromatic carbons can be found in the literature since 1994. However, lithiation on benzene carbons of 6-chloro-2,3-dimethoxyquinoxaline was reported <1999T5389>. 

Schultze, M. O., Metallic elements and blood formation, Physiol. Rev.,... 

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