High Pressure in Organic Synthesis Influence on Selectivity

High Pressure in Organic Synthesis Influence on Selectivity 

Today high pressure is routinely used especially for sensitive compounds, for example in the total synthesis of reveromycin A described by Shimizu. The sterically-hindered tertiary alcohol 5 was treated with monoallyl succinate 6 under 

On the other hand, high pressure can also be employed for the improvement of chemo-, regio-, diastereo- and enantioselectivity. In this chapter, the influence of high pressure on stereoselectivity will be the main theme, but some newer examples relating to regio- and chemoselectivity will also be presented. Several excellent books and reviews on the application of high pressure in synthesis have appeared and should be consulted for details of the pioneering work in this field [21, 22]. 

There are two different basic approaches in the control of selectivity in chemical transformations. In a kinetically controlled reaction the difference between the volumes of activation leading to the isomers must be considered, whereas in a thermodynamically controlled reaction the difference in the volumes of reaction is important. 

Clearly, a difference between the volumes of reaction does not exist for enantiomers, but also in the case of diastereomers it is usually too small to observe a 

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For general overview about the concept, see (a) L. F. Tietze, P. L Steck, High Pressure in Organic Synthesis. Influence on Selectivity, in High Pressure Chemistry, (Eds. R. van Eldik, F.-G. Klamer), Wiley-VCH, Weinheim 2002, pp. 239-283 (b)... 

I 8 High Pressure in Organic Synthesis Influence on Selectivity Tab. 8.1. Typical A V values of organic reactions. 

I 8 High Pressure in Organic Synthesis Influence on Selectivity... 

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