Immobilization of Enzymes Cross-linked Enzyme Aggregates CLEAs

Alternatively, an insoluble fluorous support, such as fluorous silica [43], can be used to adsorb the fluorous catalyst. Recently, an eminently simple and effective method has been reported in which common commercial Teflon tape is used for this purpose [44]. This procedure was demonstrated with a rhodium-catalyzed hydrosilylation of a ketone (Fig. 9.27). A strip of Teflon tape was introduced into the reaction vessel and when the temperature was raised the rhodium complex, containing fluorous ponytails, dissolved. When the reaction was complete the temperature was reduced and the catalyst precipitated onto the Teflon tape which could be removed and recycled to the next batch. 

Immobilization of Enzymes Cross-linked Enzyme Aggregates (CLEAs) 

A CLEA prepared from CaLB was recently shown to be an effective catalyst for the resolution of 1-phenylethanol and 1-tetralol in supercritical carbon dioxide in continuous operation [47]. Results were superior to those obtained with Nov 435 (CaLB immobilized on a macroporous acrylic resin) under the same 

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