Nitric oxide insertion reactions

Still more problematic is the apparent migratory insertion of nitric oxide into transition metal-carbon bonds, an important reaction in metal nitrosyl complexes and one that may be relevant to biochemical reactions (7). On the evidence of isotopic labeling and kinetic experiments, the insertion of NO into the C0-CH3 bond of the (cyclopentadie-nyl)cobalt complex (i75-C5H5)Co(NO)(CH3), which occurs in Reaction (3),... 

Nitric oxide (NO) reacts with organoiron(IIl) porphyrins to form six-coordinate adducts, Fe(Por)(R)(NO), Other small molecules (Oi. SO2. CO) react by insertion into the Fe—C bond, although the nature of the reaction and the stability of the products varies greatly with both the molecule itself and the organoiron group. 

Insertion reactions of sulphur dioxide and nitric oxide have also been observed with [(7i-Cp)2Zr(Cl)Me] and [(rc-CplaZrlCp)]." ... 

Silylated triphosphanes and triphosphides, synthesis, 31 188-194 yields, 31 194 Silylenes, 29 2-6 addition reactions, 29 4-6 to butadiene, 29 4 to ethylene, 29 4 to hexadienes, 29 5 mechanism, 29 4 nitric oxide scavenging, 29 4 complexes, 25 37, 51, 116, 118 as catalyst intermediates, 25 118 extrusion from disilanes, 25 114, 118 halides, 3 225 from hydridosilanes, 25 14 insertion into element-hydrogen bonds, 29 3-4... 

Comparable insertions occurred when methylmetal derivatives were exposed to NO, yielding N-alkyl-N-nitrosohydroxylaminato compounds (equation 35).342 Nitric oxide may however also behave as an oxidant, and the reactions are sometimes more complicated (Section 34.2.6.3).343... 

Nitric oxide insertion and other reactions involving coordinated ligands 115... 

The reaction of Co(tc-Cp)(CO)2 and of [Co(7t-Cp)NO]2 with nitric oxide in the presence of norbornene has been reported. In both cases the species shown in Figure 14 may be isolated in high yield.125 The mechanism of these three component syntheses could well be related to that of the NO insertion reactions (Scheme 2) in that here NO insertion might occur into the metal-carbon tt-bond of a cobalt-norbornene intermediate. 

The processes going on inside this ceramic catalytic converter include the reactions shown in the insert. Fragments of unburned hydrocarbons and carbon monoxide and nitric oxide molecules are converted to less noxious substances, such as nitrogen and carbon dioxide, by reactions at the surface of the catalyst. 

Organic isocyanates and isothiocyanates as well as nitric oxide insert similady (412). Carbon monoxide inserts to yield very stable acyltitamums (412,413). Miscellaneous Reactions of CpfTi Derivatives. Coupling of fluxional pentadienide ion with allyl bromide is regiospecificatly catalyzed by Cp2TiCl2 (414,415). In contrast, cuprous chloride gives the linear triene ... 

Okay. These are the reactions we want to happen, and they do happen somewhat as the byproducts of the engine leave the exhaust. The problem is that they don t happen all that quickly, leaving bad stuff heading out into the atmosphere. That s why we use catalysts that lower the activation energies for these reactions and help them proceed at a rapid rate. A catalytic converter is inserted in the exhaust system of a car so that it receives the bad stuff after it s left the engine. The catalytic converter contains a ceramic core coated with very expensive metals—platinum, rhodium, and palladium—and has two sections. The first section deals with nitrogen oxide and nitric oxide. 

The effect of electrical fields on the radiolysis of ethane has been examined by Ausloos et and this study has shown that excited molecules contribute a great deal to the products. The experiments were conducted in the presence of nitric oxide, and free-radical reactions were therefore suppressed. The importance of reactions (12)-(14) was clearly demonstrated by the use of various isotopic mixtures. Propane is formed exclusively by the insertion of CH2 into C2H6 and the yield is nearly equal to the yield of molecular methane from reaction (14). Acetylene is formed from a neutral excited ethane, probably via a hot ethylidene radical. Butene and a fraction of the propene arise from ion precursors while n-butane appears to be formed both by ionic reactions and by the combination of ethyl radicals. The decomposition of excited ethane to give methyl radicals, reaction (15), has been shown by Yang and Gant °° to be relatively unimportant. The importance of molecular hydrogen elimination has been shown in several studies ° °. ... 

Topics of this section include 1,2-insertion reactions of acetylenes (b), olefins (c), allenes (d), oxygen (e), carbon dioxide (f), sulfur dioxide (g), sulfur trioxide (h), and nitric oxide (i). 

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