1,3,3,3-Tetrafluoropropene
1,3,3,3-Tetrafluoropropene is a hydrofluoroolefin which has two isomers:

 cis-1,3,3,3-tetrafluoropropene.
 trans-1,3,3,3-tetrafluoropropene, used as a refrigerant (R-1234ze(E).)

References

Fluoroalkenes
Trifluoromethyl compounds
Hydrofluoroolefins