Disclosed is a process for the synthesis of fluorinated olefins, and in particularly preferred embodiments tetrafluorinated olefins having F on an unsaturated, non-terminal carbon, such as 2,3,3,3-tetrafluoropropene. The preferred processes of the present invention in accordance with one embodiment generally comprise: (a) reacting a compound of formula (I) X1X2  (I) with a compound of formula (II) CX1X2X3CX1═CX1X2  (II) to produce a reaction product comprising a compound of formula (III) CF3CHX1CH2X2  (III), and (b) exposing said compound of formula (III) to reaction conditions effective to convert said compound of formula (III) to a compound of formula (IV) CF3CZ═CH2  (IV) wherein X1, X2, and X3 are each independently selected from the group consisting of hydrogen, chlorine, bromine, fluorine and iodine, provided that X1 and X2 in formula (I) are not both hydrogen and Z is Cl, I, Br, or F.