CATALYSIS OF COMPLEXES .45. PREPARATION OF C-12 ALLYLNICKEL(II) FLUORIDE [NI(C12H9)F]X AND ITS TRANSFER TO ETA(3),ETA(2),ETA(2)-DODECA-2(E),6(E),10(Z)-TRIEN-1-YL-NICKEL(II)-TRIS(PENTAFLUOROPHENYL)FLUOROBORATE [NI(C12H19)]FB(C6F5)3, A CATALYST FOR 1,4-CIS-POLYMERIZATION OF BUTADIENE WITH NI-F COORDINATION

The C-12-allylnickel(II) fluoride [Ni(C12H12)F]x, 1, was prepared by partial protolysis of [Ni(C12H18)] with HF in Et2O at low temperature. The analytically-pure compound could be transformed, in THF or Et2O at -30-degrees-C, into the eta3,eta2,eta2-dodeca-2(E),6(E),10(Z)-trien-1-yl-nickel(II)-tris(pentafluorphenyl)fluoroborate [Ni(C12H19)]FB(C6F5)3, 2, by treatment with B(C6F5)3. The resulting complex was characterized extensively NMR spectroscopically and by an X-ray diffraction study. The anion B(C6F5)3F- is coordinated to the nickel by a relatively short Ni-F bond of 2,68 angstrom. As a consequence there of the complex catalyses the 1,4-cis polymerization of butadiene with lowered activity but with increased life time. The mechanistic importance of the Ni-F coordination is discussed in the framework of our reaction model for the allyl nickel complex catalyzed butadiene polymerization.