Synthesis from alcohols

AUyl transfer reactions, 73, 1 Allylic alcohols, synthesis from epoxides, 29, 3 by Wittig rearrangement, 46, 2 Allylic and benzylic carbanions, heteroatom-substituted, 27, 1 Allylic hydroperoxides, in... 

TABLE 10. Chlorohydrin and acetoxy alcohol synthesis from olefins with BTSP, TMSX and... 

Alcohol Synthesis from Carbon Oxides and Hydrogen on Palladium and Rhodium Catalysts... 

Reaction I Alcohol synthesis from a Grignard reagent... 

Methanol synthesis from CO and H2. Higher alcohol synthesis from CO and H2 are also included in this subclass. .. 

The presence of metallic Mo and MoOt on Si0 was found to be a prerequisite to the development of activity and selectivity for alcohol synthesis from C0-Hj. The gradual increase in alcohol production during the reaction is ascribed to the formation of CO-reduction induced defects on MoC. Experiments performed by adding olefins.to CO-H2 revealed that CO insertion into a metal-alkyl like bond constitutes the reaction pathway to alcohols. The role of K and Cl in the promotion of alcohol production is discussed. 

By a similar mechanism to that proposed for the formation of ethyl ether by dehydration of ethanol, it is possible that the reaction occurs stepwise with the intermediate dehydration of one ethanol molecule to form ethylene which then reacts with another ethanol molecule to form butanol. It is thus possible that higher alcohols may be built up by the reaction of olefins with the lower alcohols. Mixed oxide type of catalysts are used in the process of a nature similar to those which have been found effective in alcohol synthesis from hydrogen and carbon monoxide. It should lie noted here that catalysts which promote the union of carbon atoms must be used, and since potassium oxide promoted catalysts composed of mixtures of zinc, copper, or chromium oxides have been found to be effective in the syuthesis of higher alcohols, such catalysts should be useful in promoting the addition of olefins to alcohols or other oxygenated organic molecules.77... 

Scheme 8.11. (a) Group-selective ring-opening of meso epoxides by nucleophiles leads to enantioselective syntheses of 1,2-difunctionalized compounds, (b) Azido alcohol synthesis from epoxides and trimethylsilyl azide as catalyzed by (salen)CrCl complexes (see Scheme 8.6a for general structures of salen catalysts)... 

Hydroboration was discovered by Professor Herbert C. Brown (1912-2004). This reaction is so useful in synthesis that Brown s work earned him a Nobel Prize in 1979. We will describe here only one practical example of hydroboration, a two-step alcohol synthesis from alkenes. 

A. Kiennemann, J. P. Hindermann, and R. Breault, ACS Symp. Ser, 1987, 328, 237-249. Alcohol Synthesis from Carbon Oxides and Hydrogen on Palladium and Rhodium Catalysts—Study of Active Species. 

Nguyen, T.T., Zahedi-Niaki, M.H., Alamdari, H., and Kaliaguine, S. (2007) Co-Cu metal alloys from LaCoi 4Cu4,03 perovskites as catalysts for higher alcohol synthesis from syngas. Int.. Chem. React. Eng., 5 (1), 1583. 

Xiao-man, W., Yan-yan, G., Hui. L., et al. (2007). Co-Modified multiwall carbon nanotubes as promoter of Co-Mo-K catalyst for low-carbon alcohol synthesis from synthesis gas, Ziran Kexueban, 46, pp. 445-450. 

Mechanism of the Alcohol Synthesis from Esters and Grignard Reagents... 

Based on mechanistic and kinetic studies of the higher alcohol synthesis from synthesis gas, it has been shown that the ethanol in the mixed-oxygenate product is produced from intermediates derived from methanol, not CO [103,109]. Kinetic models of the synthesis have been developed that are able to explain the observed product distribution [110,111]. These models are based on a detailed understanding of the reaction mechanism in which two types of reactions dominate aldol condensation, which yields primarily 2-methyl branched alcohols, and Cl coupling reactions, which yield linear alcohols [106,111]. Estimates of the parameters of the kinetic models that quantitatively describe the oxygenate product distributions suggest that the rate of ethanol formation is about an order of magnitude lower than the rate of production of branched alcohols [111,112]. On the Cs/Cu/Zn catalysts, this results in a minimum in yield of ethanol compared with the yields of methanol, 1-propanol, and 2-methyl-1 propanol. Althou methanol conversion to ethanol has been confirmed as part of the hi er alcohol synthesis from synthesis gas, this synthesis does not offer a plausible route for the conversion of methanol to ethanol. Under the reaction conditions methanol rapidly decomposes, even at a pressme of 0.1 MPa [113], to yield an equilibrium mix of methanol, CO, and H2. Furthermore, as shown by the data in T able 7, the yield of ethanol remains low even with methanol in the feed. 

Table 8 Higher Alcohol Synthesis from Methanol and Synthesis Gas over K/CoS/MoS2 Cata tsa...

The utilization in catalysis of non-swelling basic silicates such as chrysotile and talc are briefly reviewed. Their preparations by hydrothermal synthesis for new applications in catalysis are described. They lead to original Co-Cu catalysts for alcohols synthesis from syngas and to Li/Mg0-Si02 systems active in the oxidative coupling of methane. 

PREPARATION OF Co-Cu/CHRYSOTILE CATALYSTS FOR THE ALCOHOLS SYNTHESIS FROM CO/Hg... 

G. Bian, L. Fan, Y. Fu and K. Fujimoto. High temperature calcined K-MoOj/y-AljOj Catalysts for mixed alcohol synthesis from syngas Effect of Mo loading. Appl. Catal., A 170,1998, 255-268. 

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