Toward Metal-Mediated C−F Bond Formation. Synthesis and Reactivity of the 16-Electron Fluoro Complex [RuF(dppp)₂]PF₆ (dppp = 1,3-Bis(diphenylphosphino)propane)

Abstract

The five-coordinate fluoro complex [RuF(dppp) 2 ]PF 6 (1a) has been prepared by reacting [RuCl(dppp) 2 ]PF 6 (1b) with TlF (dppp ) 1,3-bis(diphenylphosphino)propane). An X-ray investigation of 1a shows a distorted trigonal bipyramidal geometry (Y-shaped). The 16electron complex 1a reacts with a number of donors, including CO, H 2 , and F -. The X-ray structure of trans-[RuF(CO)(dppp) 2 ]PF 6 (2aBPh 4 ) suggests that the π-donor ability of the fluoro ligand is only slightly higher than that of chloride. The reaction of 1a with [Me 4 N]F gives cis-[RuF 2 (dppp) 2 ] (3), a rare difluoro complex not stabilized by π-acidic co-ligands. The Ru-F bond of 1a is hydrogenolyzed upon reaction with H 2 to give [RuH(η 2 -H 2 )(dppp) 2 ] + . The coordinatively unsaturated complex 1a reacts with activated haloalkanes R-X (X ) Cl or Br) in 1:1 molar ratio to give the fluorinated organic derivative and [RuX(dppp) 2 ] + . The halide metathesis proceeds instantaneously and quantitatively with (E)-3-bromo-1,3diphenylpropene and chlorotriphenylmethane. Substrate conversion decreases with decreasing substitution at the halogen-bearing carbon atom.

Synthesis and Reactivity of Ru(NHC)(dppp)(CO)H2 and Ru(NHC)(dppp)(CO)HF Complexes: C–H and C–F Activation

“…The compound displayed a distorted-octahedral geometry with the two, trans-phosphanes being tilted towards the hydrido ligand [P(1)-Ru(1)-P(3) 168.09(3)°; P(4)-Ru(2)-P(5) 171.20(3)°]. [12,13] The Ru-F bond lengths for the two molecules in the unit cell [2.1005(18), 2.0943(18) Å] are comparable to other hydrido fluorido Ru complexes in the literature [14,15] and in fact identical to the Ru-F distance in [Ru(PPh 3 ) 3 (CO)HF] [9] (unsurprisingly given that in both cases the π-donor fluorido ligand is trans to the π-acceptor CO group).…”

Insertion of CS2 into Iridium–Fluorine Bonds

“…[5] Catalytic procedures often allow a nucleophilic or electrophilic fluorination under mild reaction conditions and considerable progress has been made in the last decade. [6,7] A fluorination step to form a CÀF bond generally proceeds either by a transition-metal fluorido complex as an intermediate or by fluorination of a ligand. For the former pathway reductive elimination can lead to CÀF bonds.…”

The First Open‐Paddlewheel Structures in Diruthenium Chemistry: Examples of Intermediate Magnetic Behaviour between Low and High Spin in Ru25+ Species

“…[18] The distances Cu À F in those examples are very long (2.502(5)-2.693(2) ) and, therefore, the BF 4 À groups are considered as semicoordinated. However, in complex 4·THF the RuÀF bond lengths are very short (2.069(11) and 2.099 (12) ) and comparable to the length found in several ruthenium complexes in which the fluoride is a terminal ligand: 2.069(2) in [RuF(CO)A C H T U N G T R E N N U N G (dppp) 2 ]PF 6 , 2.069(3) and 2.056(3) in [Ru 2 F 2 A C H T U N G T R E N N U N G (dppp) 2 ] (dppp = 1,3-bis(diphenylphosphino)propane), [19] or 2.065 (1) …”