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Lithium promoters

Lithium, promotion of carbon monoxide oxidation, 74, 293 Long range effects, 189... [Pg.571]

Ito T, Wang J, Lin CH, Lunsford JH. Oxidative dimerization of methane over a lithium-promoted magnesium oxide catalyst. J Am Chem Soc. 1985 107 5062-8. [Pg.350]

Diaza[12]coronand-4 (21) was condensed with diethylene glycol bismesylate 22 in the presence of butyllithium. Precipitation, occuring during the reaction course, afforded the proton cryptate 24 H+ c= [1.1.1] in 40% yield. It should be noted that [1.1.1] was obtained only in 10% yield via the high-dilution method 23). Lithium promoted cyclization was excluded (as an alternative mechanism) by an additional experiment in which KH served as a base instead of BuLi. Identical yield was achieved, indicating that intramolecular hydrogen bonding was responsible of the cyclization. [Pg.188]

Non-isothermal kinetic studies [69] of the decomposition of samples of nickel oxalate dihydrate doped with Li and Cr showed no regular pattern of behaviour in the values of the Arrhenius parameters reported for the dehydration. There was evidence that lithium promoted the subsequent decomposition step, but no description of the role of the additive was given. [Pg.193]

Table I lists NO conversions (to any and all products) and rates of N2 formation obtained for these catalysts as well as TOFs of NO reduction to N2 on some of the samples. The rates of N2 formation in terms of pmole N2/s m7 on the Li/MgO catalpts are almost 5 times higher than that on pure MgO. Clearly the presence of lithium promotes NO reduction however, rates of N2 formation are not a strong function of lithium loading. In fact, very similar results were observed with all three Li/MgO samples. Under identical conditions, La203 is much more active than MgO and 4%Li/MgO, especially in the presence of O2 for example, the rates of N2 formation... Table I lists NO conversions (to any and all products) and rates of N2 formation obtained for these catalysts as well as TOFs of NO reduction to N2 on some of the samples. The rates of N2 formation in terms of pmole N2/s m7 on the Li/MgO catalpts are almost 5 times higher than that on pure MgO. Clearly the presence of lithium promotes NO reduction however, rates of N2 formation are not a strong function of lithium loading. In fact, very similar results were observed with all three Li/MgO samples. Under identical conditions, La203 is much more active than MgO and 4%Li/MgO, especially in the presence of O2 for example, the rates of N2 formation...
The synthesis of diarylmethanol-based 1,4-diols and enantiomerically pure 1,1-bi-2-naphthol (BlNOL)-derived diols has been reported via a neighbouring lithium-promoted [1,2]-Wittig rearrangement (Scheme 51). ... [Pg.496]

Silica gel structure is destroyed and the amorphous silica crystallizes at quite low temperature when 5 mole % of the alkali metal oxides is present. Lithium promotes crystallization to quartz, and sodium to cristobalite, at only 700 C. Potassium acts almost as rapidly at 700 C (354). The surface area of such alkali-containing gel drops almost to zero at 650-700 C (355). When the gel is taken at an intermediate stage as it shrinks, and is treated with acid, washed, and dried, it contains very wide pores, 300-1200 A diameter. Also there are micropores which are probably left after the sodium is extracted from the thin glassy layer on the.surface. Any surface area from 70 to 6 m g can be obtained by cooling the sample at the right point. [Pg.548]

Fig. 27 Lithium promoted reaaion of a magnesiated substrate with an aldehyde... Fig. 27 Lithium promoted reaaion of a magnesiated substrate with an aldehyde...
The mixed vanadium pentoxide/phosphorous pentoxide (with niobium, copper, lithium promoters) catalyst used by Petrotex was, at the time, a further step change in the catalyst types used for hydrocarbon oxidatiom It also eventually contributed to a better understanding of the catalyst structures used in oxidation reactions. The catalyst must have evolved from the accumulated experience obtained with a variety of mixed oxide catalysts and had a composition similar to that shown in Table 4.8. Distillers patented a molybdenum triox-ide/phosphorous pentoxide catalyst, and the Atlantic Refining Company took out a patent for a vanadium pentoxide/phosphorous pentoxide catalyst specifically for butene-2 oxidation. The vanadiitm pentoxide catalyst gave higher yields. [Pg.145]

Here there is a product-forming reaction between lithium acetate and acetyl iodide. This is then followed by the reaction between lithium iodide and methyl acetate. The lithium-promoted pathway increases the overall rate of product formation by about 10 times and makes the manufacturing process commercially viable. [Pg.105]


See other pages where Lithium promoters is mentioned: [Pg.221]    [Pg.118]    [Pg.24]    [Pg.133]    [Pg.118]    [Pg.131]    [Pg.118]    [Pg.110]    [Pg.1126]    [Pg.188]    [Pg.41]    [Pg.160]    [Pg.168]    [Pg.395]    [Pg.396]    [Pg.16]    [Pg.6]    [Pg.494]    [Pg.567]    [Pg.323]    [Pg.4]    [Pg.62]    [Pg.508]   


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Monsanto process lithium iodide promoter

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