Selective Formation and Characterization of a Rh^III Difluorido λ⁴‐Trifluorosulfanyl Complex

Abstract

A general route to access the Vaska type fluorido complexes (6), Ph (7), iPr (8), Cy (9), tBu (10)] was developed by treatment of trans-[Rh(Cl)(CO)(PR 3 ) 2 ] (1-5) with Me 4 NF. The molecular structures of 8 and 9 were determined by

Versatile Reaction Pathways of 1,1,3,3,3‐Pentafluoropropene at Rh(I) Complexes [Rh(E)(PEt3)3] (E=H, GePh3, Si(OEt)3, F, Cl): C‐F versus C‐H Bond Activation Steps

“…The three signals for the fluorido ligands appear at −336.9, −297.9 and −271.3 ppm as broad quartet‐like features with coupling values up to 160 Hz due to couplings presumably to the other two fluorido ligands in a cis position and a respective phosphorus atom in the trans position. The values of the couplings are in accordance with literature [11b,17c,18] . The two resonances corresponding to the CF 2 moiety appear at −84.8 and −94.3 ppm as doublet of multiplets and doublet of doublet of quartet of doublet of doublets with a geminal F,F coupling of 98 Hz, which is a bit larger than the corresponding value for complex 2 and indicates some C(sp 3 ) character.…”

“…The values of the couplings are in accordance with literature. [ 11b , 17c , 18 ] The two resonances corresponding to the CF 2 moiety appear at −84.8 and −94.3 ppm as doublet of multiplets and doublet of doublet of quartet of doublet of doublets with a geminal F,F coupling of 98 Hz, which is a bit larger than the corresponding value for complex 2 and indicates some C(sp 3 ) character. The latter signal couples to a rhodium‐bound fluorido ligand as well as the CF 3 moiety, rhodium and the phosphorus.…”

“…These values for coupling constants are typical for binuclear rhodium complexes with halogenido bridges as well as phosphines in a trans position to a fluorido ligand, while the chemical shifts are similar to other binuclear rhodium‐halogenido bridged complexes bearing triethylphosphane. [ 7c , 11b , 17 ] The 19 F NMR spectrum of 9 exhibits eight resonances which correlate in the 19 F, 19 F gCOSY NMR spectrum demonstrating that all belong to the same complex (Figure 3 ).…”

Reactivity of Binary and Ternary Sulfur Halides towards Transition‐Metal Compounds

“…Furthermore, neither the variation of the halido ligand by using trans ‐[Ir(X)(CO)(PEt 3 ) 2 ] [X=Br ( 120 a ), I ( 120 b )] nor employment of trans ‐[Rh(X)(CO)(PEt 3 ) 2 ] [X=Br ( 121 a ), I ( 121 b )] as starting materials led to a better selectivity, but instead to a lower stability of the SF 3 ‐complexes in the product mixture . Nevertheless, cis , trans ‐[Rh(F) 2 (SF 3 )(CO)(PEt 3 ) 2 ] ( 122 ) was generated exclusively by a reaction of the fluorido complex trans ‐[Rh(F)(CO)(PEt 3 ) 2 ] ( 123 ) with SF 4 (Scheme ) . This transformation further confirms the strong influence of the halido ligand on the selectivity of the reactions.…”

“…In contrast, a tetrahedral arrangement at the sulfur atom is in accordance with a formal 3‐electron donation to the metal center . Calculations on the experimentally known complexes trans ‐[Ir(Cl)(F)(SF 3 )(CO)(PEt 3 ) 2 ] ( 119 ) cis , trans ‐[Rh(F) 2 (SF 3 )(CO)(PEt 3 ) 2 ] ( 122 ), and trans ‐[Pt(F)(SF 3 )(PR 3 ) 2 ] [R= i Pr ( 125 a ), Cy ( 125 b )] revealed a pseudo‐square‐pyramidal (trigonal‐bipyramidal) coordination of the sulfur atom, which was also suggested based on variable temperature NMR spectroscopic data …”