4-(2,4-Dioxo-3-propyl-1,5-dioxaspiro[5.5]-undecan-3-yl)-2,3,5,6-tetrafluorobenzonitrile is a substituted Meldrum′s acid derivative. It can be prepared by reacting pentafluorobenzonitrile with 3-propyl-1,5-dioxaspiro[5.5]-undecane-2,4-dione.This compound undergoes cycloreversion to form the fluoro(hetero)aryl ketene, which undergoes efficient coupling with nucleophiles and allows rapid incorporation of highly fluorinated α-fluoro(hetero)aryl acetic acid derivatives.