Phytol, dehydration

Dehydrative condensation. Hirschmann, Miller, and Wendler developed an improved synthesis of vitamin Ki involving condensation of phytol with the 1-mono-acetate of 2-methyl-1,4-naphthohydroquinone in dioxane at 76° in the presence of... 

Branched alkenes from zooplankton Phytol-derived olefinic hydrocarbons have been isolated in low concentration from marine zooplankton (1) isomeric mono-olefins from mixed zooplankton from the Gulf of Maine by Blumer and Thomas (1965b) (2) isomeric phytadienes derived by dehydration of phytol, presumably by acid catalysis (Blumer and Thomas, 1965a) (3) C19 di- and tri-olefinic hydrocarbons (Blumer et al., 1969). These olefins are not present in ancient sediments and in petroleum and are therefore valuable markers in the distinction between marine hydrocarbons from organisms and from oil pollution. 

If cholesterol esters are esterified directly and the free cholesterol is not removed prior to GC analysis, it may dehydrate to form cholestadiene on the column and this may obscure some of the C22 components [499]. Similarly, cholestadiene and cholesterol methyl ether are generated to some extent when most acidic reagents are used for transesterification, and analogous by-products are formed from plant sterols [376,494,626,835]. This does not occur with base-catalysed transesterification. Other hydrolysis products of low molecular weight from lipids, such as phytol and aldehydes, can be troublesome in some... 

Phytol formed by hydrolysis of chlorophyhs can further dehydrate to various phytadienes, an example of which is neophytadiene (9-18). Microbial degradation of phytol in the rumen of ruminants gives branched fatty acids (see Section 3.3.3.3.2). 

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