O=C([C-]=C([O-])C(F)(F)F)C(F)(F)F	152	Strange valence at C
CC([O-])=[C-]C(=O)C(F)(F)F	153	Strange valence at C
O=S(F)(F)(F)F	163	Strange valence at S
ClC(=[Cl+])N1CCOCC1	374	Strange valence at Cl