High selectivity process to make dihydrofluoroalkenes

Disclosed is a method for the synthesis of fluorinated alkenes comprising contacting a fluorinated alkyne of the formula R1 C=C R2, wherein R1 and R2 are independently selected from CF3, C2F5, C3F7, and C4F9, in a pressure vessel, with a Lindlar catalyst, with substantially one molar equivalent of hydrogen, to make the corresponding cis-alkene of formula R1 C=C R2 with high selectivity, wherein said hydrogen is added in portions over a period of time, so as to produce an initial pressure in the pressure in the vessel of no more than about 100 psi.