Reactions of low-valent metal complexes with fluorocarbons. Part VII. Bis(triphenylphosphine)(π-ethylene)nickel and tetrakis(methyldiphenylphosphine)nickel
Abstract
Bis(triphenylphosphine)(π-ethylene)nickel reacts with hexafluoroacetone to form (Ph3P)2Ni[(CF3)2CO], and with chloro- and bromo-trifluoroethylene to give the vinyl complexes trans-(Ph3P)2Ni(CF:CF2)X [X = Cl or Br]. A cis–trans mixture of 1,2-dichloro-1,2-difluoroethylene reacts similarly forming a mixture of trans-(Ph3P)2Ni(cis-CF:CFCl)Cl and trans-(Ph3P)2Ni-(trans-CF:CFCl)Cl. Analogous reactions take place with tetrakis(methyldiphenylphosphine)nickel. Hexafluoropropene, hexafluorocyclobutene, 1,1-difluoroethylene, and monofluoroethylene displace ethylene from (Ph3P)2Ni(C2H4) to afford (Ph3P)2Ni(fluoro-olefin) complexes; whereas trifluoroethylene gives the compound (Ph3P)2Ni(CF2CFH)2, postulated to contain a five-membered C4Ni ring. The nickel(III) complexes (Ph3P)2Ni(RF)l2(RF= CF3 or C3F7) are formed when RFl is reacted with (Ph3P)2-Ni(C2H4). Pentafluorobenzoyl chloride reacts with (Ph3P)2Ni(C2H4) to form (Ph3P)2Ni(C6F5)Cl.