341. Chemistry of the metal carbonyls. Part XXV. Flurocarbon derivatives of nickel

Abstract

Both are air-stable.

π-Perfluoroallyltricarbonylcobalt: Synthesis and Reaction with Triphenylphosphine

“…The 19F n.m.r. spectrum (see Table 1) is similar to those of other o-perfluoropropenyl complexes studied (1)(2)(3) having a trans configuration3 about the C=C bond (7) (JFnFa = 147 Hz).…”

“…Attempts which may have yielded such a complex gave only o-perfluoropropenyl or o-perfluoroallyl (1)(2)(3) complexes. Perfluororcyclic ligands have been reported to bond to iron (4) and cobalt (5) through a n-ally1 linkage.…”

Transition-Metal-Free Formation of C–E Bonds (E = C, N, O, S) and Formation of C–M Bonds (M = Mn, Mo) from N-Heterocyclic Carbene Mediated Fluoroalkene C–F Bond Activation

“…15 There are several examples of transition-metal complexes bearing [M]–C(F)=C(F)(CF 3 ) perfluorovinyl ligands, 25 but there have been fewer reports on the [M]–C(CF 3 )=CF 2 form, wherein the trifluoromethyl substituent is on the carbon bound directly to the metal. 25f,26 In this work, the terminal F trans to the metal in traditional fluorovinyl complexes has effectively been replaced by an imidazolium fragment.…”

“…15 There are several examples of transition-metal complexes bearing [M]–C(F)=C(F)(CF 3 ) perfluorovinyl ligands, 25 but there have been fewer reports on the [M]–C(CF 3 )=CF 2 form, wherein the trifluoromethyl substituent is on the carbon bound directly to the metal. 25f,26 In this work, the terminal F trans to the metal in traditional fluorovinyl complexes has effectively been replaced by an imidazolium fragment. Consequently, the C=C bond length in 11 is comparable to that in an analogous Ni-based 26a (1.318(6) Å) perfluorovinyl complex but longer than that in an Ir-based complex 26b (1.22(3) Å) reported by Hughes et al Replacement of a terminal F by this imidazolium fragment forms what can be viewed as a push–pull alkene type of system.…”

“…Consequently, the C=C bond length in 11 is comparable to that in an analogous Ni-based 26a (1.318(6) Å) perfluorovinyl complex but longer than that in an Ir-based complex 26b (1.22(3) Å) reported by Hughes et al Replacement of a terminal F by this imidazolium fragment forms what can be viewed as a push–pull alkene type of system. 27 Unfortunately, comparisons to reports on Rh 25f and Fe examples 26c cannot be made due to the lack of X-ray crystal structure data.…”