Alkene biological hydration

The fatty acid oxidation pathway comprises a sequence of steps frequently encountered in biology (1) oxidation of an alkane to produce an alkene (2) hydration of the alkene to form a hydrojcyl group and (3) oxidation of the hydroxyl group to form a kelo group. This three-step sequence is also found in the Krebs cycle and the isoJeucine catabolic pathway. 

The nse of polysnlfide complexes in catalysis has been discnssed. Two major classes of reactions are apparent (1) hydrogen activation and (2) electron transfers. For example, [CpMo(S)(SH)]2 catalyzes the conversion of nitrobenzene to aniline at room temperature, while (CpMo(S))2S2CH2 catalyzes a number of reactions snch as the conversion of bromoethylbenzene to ethylbenzene and the rednction of acetyl chloride, as well as the rednction of alkynes to the corresponding cw-alkenes. Electron transfer reactions see Electron Transfer in Coordination Compounds) have been studied because of their relevance to biological processes (in, for example, ferrodoxins), and these cluster compounds are dealt with in Iron-Sulfur Proteins. Other studies include the use of metal polysulfide complexes as catalysts for the photolytic reduction of water by THF and copper compounds for the hydration of acetylene to acetaldehyde. ... 

Notice that the conversion of citrate to cis-aconitate is a biological example of the dehydration of an alcohol to produce an alkene (Section 13.5). The conversion of cis-aconitate to isocitrate is a biochemical example of the hydration of an alkene to produce an alcohol (Sections 12.5 and 13.5). 

This reaction is a biological example of the hydration of an alkene to produce an alcohol (Sections 12.5 and 13.5). 

The general theme of this text is to focus on reactions that have a direct relevance to the chemistry of living organisms. Every so often, though, we ll discuss a particularly useful laboratory reaction that has no biological counterpart. In the present case, alkenes are often hydrated in the laboratory by two nonbiological procedures, oxymercuration and hydroboration/oxidation, which give complementary results. 

Hydration of alkenes occurs stereospecifically in biological systems. Hydration of fumarate by D2O catalyzed by fumarase yields (2S,3i )-3-deuteriomalate. Determine the stereochemistry of addition. 

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