Pentafluoroaryl transfer from tris(pentafluorophenyl)boron hydrate to nickel.: Synthesis and X-ray crystal structure of (PPh2CH2C(O)Ph)Ni(C6F5)2

The reaction of tris(pentafluorophenyl)boron trihydrate, B(C6F5)(3).3H(2)O (1), with the nickel dimer [(PPh2CH=C(O)Ph)Ni(Ph)](2) (3) (synthesized by phosphine abstraction from (PPh2CH=C(O)Ph)Ni(Ph)(PPh3) (2)) yields (PPh2CH2C(O)Ph)Ni(C6F5)(2) (4). In this reaction a number of processes occur: fragmentation of the dimer 3, transfer of two protons from 1, and transfer of two C6F5 groups from boron to nickel. In solution, 4 loses one C6F5 ligand as pentafluorobenzene due to proton transfer from the chelating ligand, forming the dimer [(PPh2CH=C(O)Ph)Ni(C6F5)](2) (5) Compounds 4 and 5 were characterized by NMR and MS techniques. Compound 4 was independently synthesized by the reaction of PPh2CH2C(O)Ph and (eta(6)-toluene)Ni(C6F5)(2). The crystal structure of 4 was determined using single-crystal X-ray diffraction methods. Details concerning the synthesis and characterization of 1-3 are also given.