Search results for "Ferrocene"
showing 10 items of 306 documents
Synthesis and electrochemical study of a new doubly-metallated compound with the ferrocene-labelled phosphine PPh2(C5H4)Fe(C5H5)
1993
Abstract Direct reaction of the metalled compound Rh 2 (μ 2 -O 2 CCH 3 ) 3 [μ 2 -(C 6 H 4 ) PPh 2 ]·(H 2 O) 2 with PPh 2 Fc [Fc = (C 5 H 4 )Fe(C 5 H 5 )] in chloroform solution yields the corresponding mono-adduct Rh 2 (O 2 CCH 3 ) 3 [(C 6 H 4 )PPh 2 ]·(PPh 2 Fc) ( 1 ), which has been characterized by 31 P NMR spectroscopy. Photochemical irradiation of 1 in chloroform gives the compound Rh 2 (μ-O 2 CCH 3 ) 2 (η 2 -O 2 CCH 3 )[μ 2 -(C 6 H 4 )PPh 2 ][PPh 2 Fc]·(H 2 O) ( 2 ) in practically quantitative yield. Compound 2 , by thermal treatment in chloroform solution, yields cleanly the doubly-metallated compound Rh 2 (μ 2 -O 2 CCH 3 ) 2 [μ 2 -(C 6 H 4 )PPhFc][μ 2 -(C 6 H 4 )PPh 2 ]·(H 2 O) 2 ( …
The Preparation of Tetramethyl 1,1′,3,3′-Ruthenocenetetracarboxylate and Tetramethyl 1,1′,3,3′-Osmocenetetracarboxylate, and a Simplified Synthesis …
2018
Substituted metallocenes with more than two substituents have to be synthesized using doubly substituted cyclopentadiene rings in a reaction with a metal compound or by the introduction of additional functional groups to an already di-substituted metallocene. The direct formation of tetra-substituted metallocenes often suffers due to insufficient reactivity of the reagents or the resulting product mixtures, which are hard to separate. In this work, a protocol, which was successful in a tetra-substitution of ferrocene by a tetra-metalation followed by a reaction with carbon dioxide, is used to perform the tetra-substitution of ruthenocene and osmocene. In addition, a simplified protocol for …
Different coordination modes of a 1,1′,2,2′-ferrocenyltetraphosphine: Bi- and tri-dentate behaviour with group 6 and 7 transition metals
2002
The behaviour of 1,1′,2,2′-tetrakis(diphenylphosphino)-4,4′-di(tert-butyl)ferrocene (1), acting as a homoannular or heteroannular ligand, has been studied. Due to the cisoid disposition of the phosphino groups of each ring, different coordination modes are observed. With group 6 metal carbonyls, M(CO)6, the tetraphosphine acts exclusively as a tridentate ligand. In contrast, the reaction with MnCp(CO)3 leads to complexes showing 1,1′ and 1,2 bidentate coordination modes. All these complexes have been characterised by 1H and 31P NMR spectroscopy. The molecular structures of the molybdenum complex [(1)Mo(CO)3] (2b) and the 1,1′ manganese complex [(1)MnCp(CO)] (3) have been established by X-ra…
Palladium-catalyzed formation of secondary and tertiary amines from aryl dihalides with air-stable ferrocenyl tri- and diphosphines: Synthesis and X-…
2014
Abstract Robust, air-stable tridentate and bidentate ferrocenylphosphines 1,2-bis(diphenylphosphino)-1′-(diisopropylphosphino)-4-tert-butylferrocene, L5, and 1,1′-bis(diisopropylphosphino)-3,3′-bis(tert-butyl)ferrocene, L9, combined with 1 mol% of [PdCl(η3-C3H5)]2 led to two new catalytic systems which allow the coupling of aniline derivatives with mono- and dihaloarenes to form functionalized diarylamines and triarylamines. The excellent selectivity of the reactions avoids the deleterious dehalogenation of the substrates and products. The X-ray structure characterization of the related complex [PdCl2(L9)] is reported in which ligand L9 in its meso form is significantly distorted.
Palladium C–N bond formation catalysed by air-stable robust polydentate ferrocenylphosphines: a comparative study for the efficient and selective cou…
2014
The arylation of aniline derivatives with dichloroarenes under a low palladium content (below the currently used 5 to 10 mol%) was studied using nine different ferrocenylphosphine ligands, including the easily accessible 1,1′-bis(diphenylphosphino)ferrocene, DPPF. The electron-enriched air-stable tridentate ferrocenylpolyphosphine 1,2-bis(diphenylphosphino)-1′-(diisopropylphosphino)-4-tert-butylferrocene, L5, employed in 2 mol% in combination with 1 mol% [PdCl(η3-C3H5)]2 allows an efficient and selective coupling, while such demanding substrates currently induce chloroarene homocoupling and/or dehalogenation processes. The scope and limitation of the optimized system are explored, with a fo…
General route to dissymmetric heteroannular-functionalized ferrocenyl 1,2-diphosphines: selective synthesis and characterization of a new class of tr…
2006
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...
Diastereoselective Synthesis of Dialkylated Bis(phosphino)ferrocenes: Their Use in Promoting Silver-Mediated Nucleophilic Fluorination of Chloroquino…
2017
International audience; The diastereoselective synthesis of dialkylated ferrocenyl bis(phosphane)s bearing aryl, alkyl, and hetero- or polycyclic substituents on the phosphino groups is reported, together with their characterization in the solid state by X-ray structure analysis and in solution by multinuclear NMR spectroscopy. Introduction of various alkyl groups on the ferrocene backbone, namely, tert-butyl, isopropyl, and trimethylsilyl, has a significant influence on the stereoselectivity of the ensuing lithiation/phosphination reactions. Only the introduction of the tert-butyl groups ensures both a high yield and perfect diastereoselectivity, which leads to the exclusive formation of t…
CCDC 142834: Experimental Crystal Structure Determination
2001
Related Article: R.Broussier, E.Bentabet, M.Laly, P.Richard, L.G.Kuz'mina, P.Serp, N.Wheatley, P.Kalck, B.Gautheron|2000|J.Organomet.Chem.|613|77|doi:10.1016/S0022-328X(00)00501-5
Three‐Component Self‐Assembly Changes its Course: A Leap from Simple Polymers to 3D Networks of Spherical Host–Guest Assemblies
2021
Angewandte Chemie / International edition 60(21), 12132 - 12142 (2021). doi:10.1002/anie.202103178
Gold(I) Complexes Nuclearity in Constrained Ferrocenyl Diphosphines: Dramatic Effect in Gold‐Catalyzed Enyne Cycloisomerization
2020
International audience; Di-tert-butylated-bis(phosphino)ferrocene ligands bearing phosphino substituents R (R=phenyl, cyclohexyl, isopropyl, mesityl, or furyl) allow tuning the selective formation of Au(I) halide complexes. Thus, dinuclear linear twocoordinate, but also rare mononuclear trigonal three-coordinate and tetrahedral four-coordinate complexes were formed upon tuning of the conditions. Both Au(I) chloride and rarer Au(I) iodide complexes were synthesized, and their X-ray diffraction analysis are reported. The significance of the control of structure and nuclearity in Au(I) complexes is further illustrated herein by its strong effect on the efficiency and selectivity of gold-cataly…