Organozinc Fluoride and Trifluoromethyl Compounds Supported by the Bis(2-pyridylthio)methyl Ligand

The bis(2-pyridylthio)methyl ligand, [Bptm], has been employed in the synthesis of {[Bptm]Zn(μ-F)} 2, a rare example of an organozinc fluoride compound. The dimeric nature of {[Bptm]Zn(μ-F)} 2, which possesses an uncommon [Zn(μ-F)] 2 motif, contrasts with the monomeric structures reported for the other halide derivatives, [Bptm]ZnX (X = Cl, Br, I); this difference is supported by density functional theory calculations which indicate that the fluoride derivative favors a dimeric form with bridging fluoride ligands, whereas the other derivatives favor monomeric structures with terminal halide ligands. {[Bptm]Zn(μ-F)} 2 reacts with Me 3 SiCF 3 to afford the organozinc trifluoromethyl complex, namely [Bptm]ZnCF 3 . The Zn–CF 3 bond in this complex is longer than the Zn–CH 3 bond of the previously reported methyl derivative [Bptm]ZnMe, an observation that is precedented in related zinc compounds but counter to other metal complexes. The infrared frequency corresponding to the asymmetric C–F stretch of [Bptm]ZnCF 3 is unusually low for a metal trifluoromethyl species but is comparable to those for other zinc and cadmium complexes.