Insertion of a Water Oxygen Atom into a Phosphorus−Metal Bond:  From a P-Coordinated (Diphenylphosphino)alkyne to a Coordinated η²(O,C)-Vinyldiphenylphosphine Oxide^†

Abstract

The reaction of [(Fp)Ph2PC⋮CR][BF4] (Fp = (C5H5)Fe(CO)2; R = H (1), Me (2), tBu (3), Ph (4), Tol (5)) with (CH3)3NO·2H2O (6) was studied, and the new complexes [CpFe(CO)(η2(O,C)-Ph2P(O)CHCR)] (R = Ph (7), Tol (8)) were isolated. Compound 8 was characterized by X-ray diffraction. An isotopic labeling study showed that the oxygen atom bonded to phosphorus came from a water molecule.

Alkynyldiphenylphosphine d8(Pt, Rh, Ir) Complexes: Contrasting Behavior towardcis-[Pt(C6F5)2(THF)2]

“…For example, [(η 5 -C 5 H 5 )Ni] 2 (PPh 2 (O)C 2 CF 3 ), the first acetylenic phosphine oxide π complex structurally characterized, was obtained as one byproduct in the reaction of [(η 5 -C 5 H 5 ) 2 Ni] with PPh 2 Ct CCF 3 . 79 More recently, a cationic iron P-coordinated (diphenylphosphino)alkyne complex [(C 5 H 5 )Fe(CO) 2 (PPh 2 CtCPh)]-(BF 4 ) was oxidized to an iron vinyldiphenylphosphine oxide 81 and the η 2 -alkynylphosphine complex [Pt(η 2 -PPh 2 CtCMe)-(dcpe)] was oxidized in air to the corresponding phosphine oxide complex [Pt{η 2 -PPh 2 (O)CtCMe}(dcpe)]. 9 To check the possibilities of insertion in other systems, we have examined the reactions of the catecholate and dithiolate complexes 6 and 7 with cis-[Pt(C 6 F 5 ) 2 (THF) 2 ] in 1:1 and 1:2 molar ratios.…”

Alkyne–phosphinoalkyne coupling reactions on mixed-metal tungsten–cobalt centres; P–C(alkyne) bond cleavage versus P–C(alkyne) bond preservation

“…Solvents were distilled under nitrogen from appropriate drying agents and degassed prior to use. 24 Infrared spectra were recorded in hexane solution in 0.5 mm NaCl cells, using a Perkin-Elmer 1710 Fourier-transform spectrometer, fast atom bombardment (FAB) mass spectra on a Kratos MS 890 instrument using 3-nitrobenzyl alcohol as a matrix, proton (reference to SiMe 4 ), 31 P and 13 C NMR spectra on either a Bruker WM250 or AM400 spectrometer; 31 P NMR chemical shifts are referenced to 85% H 3 PO 4 . Preparative thin-layer chromatography (TLC) was carried out on commercial Merck plates with a 0.25 mm layer of silica, or on 1 mm silica plates prepared at the Department of Chemistry, Cambridge.…”

Rhenium carbonyl compounds with (diphenyl)phosphinoalkynes and a sterically hindered phosphinoalkyne

“…However, further studies with a broad range of metal complexes have revealed other interesting abilities of these ligands such as the preparation of metal complexes with uncoordinated alkynes [2][3][4], intramolecular coupling of the alkynyl moieties [5][6][7], insertion of the triple bond in M-H or M-C bonds [8,9], preparation of heterometallic compounds [6,[10][11][12], or the development of new materials [13]. These ligands can also lead to the formation of metallacycles by means of a reaction between the alkyne and another ligand linked to metal [9,14,15]. We reported some years ago that cationic P-coordinated iron complexes [(C 5 H 5 )Fe-(CO) 2 (Ph 2 PC"CR)] + can lead to the formation of metallacycles in mild conditions, giving good yields by the reaction pathway shown in Scheme 1 [15].…”

“…These ligands can also lead to the formation of metallacycles by means of a reaction between the alkyne and another ligand linked to metal [9,14,15]. We reported some years ago that cationic P-coordinated iron complexes [(C 5 H 5 )Fe-(CO) 2 (Ph 2 PC"CR)] + can lead to the formation of metallacycles in mild conditions, giving good yields by the reaction pathway shown in Scheme 1 [15].…”