Asymmetric Hydrogenation of Fluorinated Olefins

Chiral organofluorides are increasingly in demand as the pharmaceutical and materials industries seek to take advantage of the special properties these halides impart. A lack of methods to provide chiral monofluorides and trifluoromethyl groups has given the group of Andersson impetus to create new asymmetric hydrogenation routes to these valuable halides [48, 49]. 

Evidently, vinylfluorides represent a new challenge to iridium asymmetric hydrogenation. It is noteworthy that no examples of asymmetric reduction of 

In contrast to normal trisubstituted aryl olefins, a strong pressure effect was observed in this case. Interestingly, for substrate 44a catalysts hydrogenation with Ir(13d) demonstrated opposite pressure-dependant enantioselectivity of substrate 45a with catalyst Ir(46). Poor enantioselectivity was obtained for substrates that did not contain an aromatic ring adjacent to the olefin. 

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