Environment-friendly couplings

In an article dealing with applications of olefin CM to a series of commercial products [138], solvent-free CM between ( )-3-hexene (produced by homocoupling of 1-butene) and 11-eicosenyl acetate 303 (produced from jojoba oil) was used to produce acetate 304 (Scheme 59), which is - as a natural 82 18 (EIZ) mixture - the pheromone of omnivorous leafroller, and serves as an environment-friendly pest controlling agent. The CM reaction was performed without solvent at 5 °C with a 4 1 mixture of ( )-3-hexene and 303, in the presence of only 0.2 mol% catalyst C, and furnished after 20 h coupling product 304 ( Z=83 17) in 50% yield. 

There are several reasons for carrying out the reactions at supercritical conditions. Naturally, some of the reasons are coupled. Nevertheless, they, in general, relate to favorable transport properties, unique solvency characteristics, favorable kinetic considerations, and their sensitivity to operating conditions (manipulated variables). These unique properties lead to opportunities in process synthesis, process intensification, and controllability. These advantages, coupled with the environmentally friendly nature of these processes, make reactions in supercritical fluids attractive. The effect of these properties on opportunities for these favorable reaction environments is summarized in Table 1. 

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