3.3- Dichloro-2-oxetanones

As can be seen in some of the above examples, the reactions of nucleophiles with /3-lactones are subject to modifications depending on the structure of the lactone. A good example can be seen in reactions of 3,3-dichloro-2-oxetanones, which react with various nucleophiles only by acylation (acyl-oxygen cleavage) (equation 57) (73JHC239). 

Dichloromethylenecyeloalkanes. Zinc dechlorination of trichloroacetyl chloride in the presence of cyclic ketones results in formation of dichloroketcne and in situ cycloaddition to give 3,3-dichloro-2-oxetanones (I). The 2-oxctanones are easily... 

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