ORGANOMETALLIC COMPOUNDS methane

Messenger-RNA mRNA) for gene cloning, 242 Mesylates. See Methanesulfonic acid, esters Metal organyls. See Organometallic compounds MethanaL See Formaldehyde Methanamine, 1,1-dimethoxy-jV.Mdiinethyi- formylation with, 82... 

Reaction of organometallic compounds with carbonyl compounds a. primary alcohols from methanal (formaldehyde)... 

In another recent study of CO reduction using organometallic compounds of the early transition elements, Caulton et al. report that CH4 is evolved when toluene solutions of (C5H5)2Ti(CO)2 are heated at 150°C under H2 or H2 -l- CO atmospheres (55). When deuterium is used, the observed product is CD4, although some deuteration of the cyclopentadienyl rings is noted. Caulton does not report the percent yield of methane, but does state that the reaction is not catalytic. One of the most novel aspects of this investigation is the isolation of a blue Tig cluster that is inert to further reaction... 

Supercritical C02 has also recently attracted much attention as a reaction medium for C-H bond activation, because C02 is miscible with organic compounds, including organometallic compounds, and potentially stable toward alkane activation conditions. We have successfully applied supercritical C02 to the carbonyla-tion and dehydrogenation of hydrocarbons [34], The technique is effective for conversion of gaseous substrates such as methane and ethane [35]. 

First, an organometallic compound is formed from dibromodifluoro-methane. Quite unexpectedly, trifluoromethyl copper is generated—who knows how ... 

The nickel-containing factor F 430 (134) provides an example of how nature exploits the reactivity of organometallic compounds, as is the case with vitamin B12. Factor F 430 (134) plays a key role as cofactor for the coenzyme M reductase of primitive methanogenic bacteria in the formation of methane from 2-(methylthio)-ethanesulfonate (86). The structural elucidation of factor F 430 (134) is based on a combination of classical spectroscopic methods, chemical degradation, and biosynthetic studies with C-labelled precursors 83a,b). These biosynthetic investigations will be addressed in section 8.2. Chemical degradation products obtained by ozonolysis of factor F 430 (134) allowed the determination of the absolute configuration by comparison with reference compounds derived from chlorophyll a (2) and vitamin B12 (4) 83a,b). 

Considerable challenges still remain in the development of new carbonylation processes for acetic acid manufacture. For example, all of the current processes use iodide compounds, leading to corrosive HI and the need for expensive materials for plant construction. An iodide-free system could potentially impart considerable benefit. Other long term goals include the selective direct conversion of syn-gas or oxidative carbonylation of methane to acetic acid. Organometallic chemists are certain to play a crucial role if these targets are to be achieved. 

Sen A (1999) Catalytic Activation of Methane and Ethane by Metal Compounds. 3 81-95 Severin K (2006) Organometallic Receptors for Biologically Interesting Molecules. 17 123— 142... 

Perrhenate and related building blocks are constituents of several cluster compounds where they act as terminal groups in organometallic rhenium oxides such as in [(cp Re)3(//2-0)3(/U3-0)3Re03]+ (49)21 Qj. jjj heterometallic clusters such as the structurally related [(Re)3(//f dppm)3(/u -0)3Re03]+ (dppm = bis(diphenylphosphino)methane) and Pt4 P(C6H 11)3)4 (//-C0)2(Re04)2]. A series of platinum-rhenium and platinum-rhenium-mercury clusters with Pt-Re multiple bonds has been isolated from reactions of Pt3 precursors with Rc207 or perrhenate. " ... 

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