Fine Chemicals Produced from Functionalized Olefins

2 Fine Chemicals Produced from Functionalized Olefins 

Methyl oleate (methyl c -q-octadecenoate) is an attractive functionalized olefin for metathesis because of its ready availability and the utility of the metathesis products. An early example is the proposed route to civetone by metathesis of methyl oleate followed by cyclocondensation (Eqs. lla,b). Civetone is a seven-teen-membered unsaturated macrocyclic ketone (d5-9-cycloheptadecen-l-one) identical with the natural compound (civet cat). It has an intense musk odour, and is therefore an attractive perfume component. 

At room temperature in the presence of a Re207/Si02-Al203 catalyst promoted with BuqSn, a mixture of isomers was obtained in 14% yield. To reduce the possibility of mtermolecular metathesis between two oleon molecules, it is necessary to perform the reaction at high dilution [35]. 

Synthesis of Pheromones and other Products via Cross-metathesis 

Cross-metathesis reactions are useful for the production of fine chemicals such as synthetic perfumes, prostaglandin intermediates, and insect pheromones. An example of the last is the cross-metathesis of ethyl oleate with 5-decene in the presence of a MoCl5/Si02/Me4Sn catalyst at 90 °C [14], or a Mo03/Si02/cyclopropane catalyst at 50 °C [16], resulting in a cisitrans mixture of ethyl 9-tetradecenoate, an insect pheromone precursor (Eq. 12). 

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