Ethyl oleate, reduction

The search for solvents led to the discovery that sodium borohydride is an excellent reducing agent for aldehydes and ketones. The search for catalysts to enhance the reducing power of sodium borohydride led to an anomalous result in the reduction of ethyl oleate. Investigation of this anomalous result led to the discovery of hydroboration. 

Complete reduction of unsaturated esters to sativated alcohols takes place when the esters are hydrogenated over Raney nickel at 50° and 150-200 atm [44] or over copper chromite at temperatures of 250-300° and pressures of 300-3 50 atm [52,1056] (p. 153). In contrast to most examples in the literature the reduction of ethyl oleate was achieved at atmospheric pressure and 270-280° over copper chromite, giving 80-90% yield of octadecanol [1074]. a.,P-Unsaturated lactones are reduced to saturated ethers or alcohols, depending... 

A novel method for production of paraffinic hydrocarbons, suitable as diesel fuel, from renewable resources was illustrated. The fatty acid ethyl ester, ethyl stearate, was successfully converted with high catalyst activity and high selectivity towards formation of the desired product, heptadecane. Investigation of the impact of catalyst reduction showed that the reduction pretreatment had a beneficial effect on the formation of desired diesel compound. The non-pretreated catalyst dehydrogenated ethyl stearate to ethyl oleate. The experiments at different reaction temperatures, depicted that conversion of ethyl stearate was strongly dependent on reaction temperature with Eact=69 kj/mole, while product selectivities were almost constant. Complete conversion of ethyl stearate and very high selectivity towards desired product (95%) were achieved at 360°C. 

Oleyl alcohol has been previously prepared only by the reduction of ethyl oleate with sodium and absolute ethyl alcohol.1 By substituting butyl alcohol for ethyl alcohol, the procedure is less time-consuming and less dangerous to carry out, and gives better yields. 

Diborane reacts with alkenes to form alkylboranes in ether solvents. This important finding apparently resulted from an observation by Brown that reduction of ethyl oleate, in ether solvents and in the presence of a Lewis acid, consumed 2.4—2.5 hydrides per mole and 3 equivalents when a larger excess of the reagent was used.3 Brown discovered that borane had added to the it bond of the alkene moiety generating a monoalkyl-... 

It has been found that the presence of a polar group in the oil molecule tends to drastically reduce its EACN. For instance, ethyl oleate EACN was found to be near 6, a considerable reduction from the expected value for the Cig chain [51,52]. Thus it can be said that the ester polar group results in a drastic reduction of the oil EACN, a characteristic... 

If the oil phase is not an alkane, but behaves similarly to an alkane, it is characterized by its equivalent alkane carbon number or EACN (136). It has been shown that on an ap-olarity scale, cyclohexane EACN is 3, alkylcyclohexane EACN is equal to its aUcyl group ACN plus 3, while benzene EACN is 0, and alkylbenzene EACN is equal to its aUcyl group ACN. As a matter of fact, the more polar the oil the lower its EACN. For instance the ethyl oleate EACN is about 6. Since it contains a chain, this means that the ester group accounts for a 12-unit reduction in the EACN. Complex hydrocarbon mixtiues can be assigned an EACN too, according to a simple mixing rule which is more or less followed (136,137). 

It is not clear at present why oils stimulate the biosynthesis of some polyene macnoiides (fungichromin and filipin) and have an inhibitoiy effect on the biosynthesis of others (89). When ethyl (Z) 16 phenyIhexadec 9-enoate, an anal(% of ethyl oleate, was added to cultures of the fungichromin producer Streptomycfs ceStdow ATCC 12625, the cultures showed a drastic reduction of fungichromin biosynthesis but produced four new polyene antibiotics (93). 

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