Fischer synthesis mechanism

Inderwildi, O.R., Jenkins, S. J., and King, D.A. 2008. Fischer-Tropsch mechanism revisited Alternative pathways for the production of higher hydrocarbons from synthesis gas. J. Phys. Chem. C 112 1305-7. 

Good evidence has been obtained that heterogeneous iron, ruthenium, cobalt, and nickel catalysts which convert synthesis gas to methane or higher alkanes (Fischer-Tropsch process) effect the initial dissociation of CO to a catalyst-bound carbide (8-13). The carbide is subsequently reduced by H2to a catalyst-bound methylidene, which under reaction conditions is either polymerized or further hydrogenated 13). This is essentially identical to the hydrocarbon synthesis mechanism advanced by Fischer and Tropsch in 1926 14). For these reactions, formyl intermediates seem all but excluded. 

First all three ester bonds and both amide bonds are hydrolyzed to carboxylic acid groups by the aqueous acid. The mechanisms for these reactions are discussed in Section 19.5. The ester hydrolyses follow the exact reverse of the Fischer esterification mechanism shown in Figure 19.3, and the amide hydrolysis occurs by a very similar mechanism. The product of these hydrolysis steps has three carboxylic acid groups and one amino group. Two of these acid groups are attached to the same carbon so that one can be eliminated as carbon dioxide by the cyclic mechanism described in Section 20.4 for the malonic ester synthesis ... 

Cyanohydrin-O-diethyl phosphates in indole chemistry 88YGK1165. Fischer indole synthesis, mechanism of 88KGS867. 

Fischer, B., Kabha, E., Gendron, F.-P., Beaudoin, A. R. Synthesis, mechanism and fluorescence properties of 8-(aryl)-3-P-D-ribofuranosylimidazo[2,1-i]purine 5 -phosphate derivatives. Nucleosides, Nucleotides Nucleic Acids 2000,19,1033-1054. 

The Ruff degradation is the opposite of the Kiliani-Fischer synthesis. Thus, the Ruff degradation shortens an aldose chain by one carbon Hexoses are converted into pentoses, and pentoses are converted into tetroses. In the Ruff degradation, the calcium salt of an aldonic acid is oxidized with hydrogen peroxide. Ferric ion catalyzes the oxidation reaction, which cleaves the bond between C-1 and C-2, forming CO2 and an aldehyde. It is known that the reaction involves the formation of radicals, but the precise mechanism is not well understood. 

As is shown in Scheme 1, the use of non-symmetrical ketones in the Fischer synthesis will result in two isomeric indoles, 4 and 5. A detailed reaction mechanism is described in refs. [6] and [7], but some important characteristics will be given here. 

J.T. Kummerand P.H. Emmett. Fischer-Tropsch Synthesis Mechanism Studies. The Addition of Radioactive Alcohols to the Synthesis Gas. J. Am. Chem. Soc. 75 5177 (1953). 

Fischer-Tropsch Synthesis. Mechanism Studies Using Isotopes... 

Fischer-Tropsch Synthesis. Mechanism Studies Using Isotopes CHaXHCH, CH3 CH-CH, + H =e=... 

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