A new strategy for the synthesis of highly functionalised fluorinated compounds by reaction of lithium dianions of carboxylic acids with perfluoroketene dithioacetals

The reaction of perfluoroketene dithioacetal with lithium dienediolates of carboxylic acids proceeds at the ω position probably through an addition to the π system followed by elimination of the vinylic fluoride. The preparative value of this reaction depends strongly on the reaction and work-up conditions. The overall process lead to highly functionalised synthons containing a trifluoromethyl group.