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(C 6 F 5 ) 3 ·3H 2 O ( 1 ), with the nickel dimer [(PPh 2 CH C(O)Ph)Ni(Ph)] 2 ( 3 ) (synthesized by phosphine abstraction from (PPh 2 CH C(O)Ph)Ni(Ph)(PPh 3 ) ( 2 )) yields (PPh 2 CH 2 C(O)Ph)Ni(C 6 F 5 ) 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 C 6 F 5 groups from boron to nickel. In solution, 4 loses one C 6 F 5 ligand as pentafluorobenzene due to proton transfer from the chelating ligand, forming the dimer [(PPh 2 CH C(O)Ph)Ni(C 6 F 5 )] 2 ( 5 ). Compounds 4 and 5 were characterized by NMR and MS techniques. Compound 4 was independently synthesized by the reaction of PPh 2 CH 2 C(O)Ph and (η 6 -toluene)Ni(C 6 F 5 ) 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.