0000000000403264
AUTHOR
Vladimir V. Ivanov
General route to dissymmetric heteroannular-functionalized ferrocenyl 1,2-diphosphines: selective synthesis and characterization of a new class of tri- and tetrasubstituted ferrocenyl compounds
Several monosubstituted-cyclopentadienyl anions (A-Li) and [1,2-bis(diphenylphosphino)-4-tert-butylcyclopentadienyl]lithium (B-Li) react with FeCl2 to afford a novel class of multidentate ferroceny...
Enlarging the family of ferrocenylphosphine dinuclear rhodium complexes: synthesis and X-ray structure of a novel “A-frame”-type trimetallic Rh/Fe/Rh complex
Abstract The symmetrically substituted ligand 1,1 ′ -bis[di(5-methyl-2-furyl)phosphino]ferrocene ( 1 ) has been obtained from the bromophosphine BrP(Fu Me ) 2 and the dilithioferrocene/TMEDA adduct. The quantitative addition of this ferrocene derivative to the tetracarbonyl dimer [(CO) 4 Rh 2 {μ-(S t Bu) 2 }] leads, through decarbonylation, to the dinuclear rhodium complex [(CO) 2 Rh 2 {μ-(S t Bu) 2 }{μ- P , P -Fc[P(Fu Me ) 2 ] 2 }] ( 2 ) in high yield. A X-ray structure [ orthorhombic , space group P 2 1 2 1 2 1 ; a =11.2982(2) A, b =13.3165(3) A, c =27.2687(7) A] and the solution multinuclear NMR characterization are reported, which show that the rare “quasi-closed bridging” A-frame struc…
"Through-space" nuclear spin-spin J(PP) coupling in tetraphosphine ferrocenyl derivatives: a (31)P NMR and X-ray structure correlation study for coordination complexes.
Herein, we report on (31)P(31)P solution-phase "through-space" nuclear spin-spin coupling constants (J(PP)) from a novel family of organometallic tetraphosphine nickel and palladium complexes. These J(PP) constants were accurately determined through NMR iterative simulation based on the second-order spectra obtained for the compounds. The corresponding solid-state X-ray structures of the complexes were determined, and the "through-space" P.P distances are reported. Due to the blocked conformation of the species in solution, a qualitative and semiquantitative experimental correlation is obtained, which links the geometric parameters and the intensity of the corresponding P.P coupling constan…
Catalytic Efficiency of a New Tridentate Ferrocenyl Phosphine Auxiliary: Sonogashira Cross-Coupling Reactions of Alkynes with Aryl Bromides and Chlorides at Low Catalyst Loadings of 10-1 to 10-4 mol %.
[structure: see text] The catalytic activity in Sonogashira cross-coupling reactions of alkynes with a variety of aryl halides (including chlorides) using a multidentate ferrocenyl phosphine is presented. The novel mixed ferrocenyl aryl/alkyl triphosphine is thermally stable and insensitive to air or moisture, and its robustness allows aryl alkynylation at 10(-1) to 10(-4) mol % catalyst loadings with TONs up to 250,000. Copper-free coupling using phenylacetylene is also accessible in good yield.
Direct arylation of heterocycles: the performances of ferrocene-based polyphosphane ligands in palladium-catalyzed C-H bond activation
International audience; The palladium-catalyzed direct arylation of alkylated- furan, thiophene, and thiazole and benzoxazole heterocycles with electronically and sterically deactivated bromoarenes was selectively and efficiently promoted by ferrocenyl polyphosphanes. In this C[BOND]H bond activation reaction of heteroaromatics, the performances of polydentate di-, tri-, and tetraphosphane ligands were compared, showing that the triphosphane 1,1′,2-tris(diphenylphosphino)-4-tert-butylferrocene 3 was the most effective for the coupling. The introduction of more electron-donating (iPr) or electron-withdrawing (furyl) groups on the phosphorus atoms did not improve the ligand performances. The …