F 2-Chloroacrylonitrile

Novel dibenzo[d,f [I,3]dioxepines have been prepared from 2,2 -biphenol <94TL9327>. Thus reaction with 2-chloroacrylonitrile fords... 

The synthetic utility of the Diels-Alder reaction has been significantly expanded in recent years by development of dienophiles which contain masked functionalities and are the synthetic equivalents of unreactive or inaccessible species. For example, a-chloroacrylonitrile shows satisfactory reactivity as a dienophile. The a-chloronitrile function in the adduct can be hydrolyzed to a carbonyl group. Thus, a-chloroacrylonitrile is serving as a ketene (CH2=C=0) equivalent. Ketene itself is not suitable as a dienophile since it has a tendency to react with dienes in a [2 -f 2]-cycloaddition rather than the desired [4 + 2] fashion. 

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