15096-68-1Relevant academic research and scientific papers
Photochemical synthesis of the tungsten(II) complex
Szymanska-Buzar, T.
, p. 85 - 90 (1989)
The photochemical oxidation of W(CO)6 to 2 with CCl4 has been used to give .The same methodology was applied in the synthesis W(II) complexes having the nitrogen ligands acetonitrile, N,N,N',N'-tetramethylethylenediamine, pyrid
Palladium(II) allylic complexes by carbene transmetalation and migratory insertion reactions: Synthesis and side reactions
Albéniz, Ana C.,Espinet, Pablo,Pérez-Mateo, Alberto
, p. 441 - 445 (2010/05/03)
New 1,1-alkoxy, aryl substituted palladium η3-allyls [Pd(μ-Br){η3-C(C6F5)(OMe)CHR1CHR2}]2 can be synthesized from [W(CO)5{C(OMe)CHR1{double bond, long}CHR2}] and a palladium perfluoroaryl complex. The allyls are formed by transmetalation of the carbene fragment followed by migratory insertion of C6F5 to the putative and highly reactive Pd carbene complex. This reaction pathway predominates in all cases, but insertion of the double bond of the tungsten alkoxyvinylcarbenes into the Pd-C6F5 bond leads to secondary products, namely C6F5(OMe)C{double bond, long}CR1CH(C6F5)R2.
Formation of a vinyliminium palladium. Complex by C-C coupling in vinylcarbene palladium aryl complexes
Albeniz, Ana C.,Espinet, Pablo,Perez-Mateo, Alberto,Nova, Ainara,Ujaque, Gregori
, p. 1293 - 1297 (2008/10/09)
Pentafluorophenyl palladium complexes 3 and 5 bearing a vinylcarbene ligand slowly decompose on heating by migratory insertion to give Pd(0) and the vinyliminium salts (Et2N=C(C6F5)CH=CHPh)X(X = Br, BF4). However, the presence of triphenylphosphine in complex 4 stabilizes 7, a compound with a C=C Pd-bound vinyliminium moiety, where there is a strong preference for the C=C versus the C=N coordination.
Reduction of CO2 and other substrates using photochemical reactions of the W2(CO)102- complex
Silavwe, Ned D.,Goldman, Alan S.,Ritter, Robin,Tyler, David R.
, p. 1231 - 1236 (2008/10/08)
The photochemistry of the W2(CO)102- complex was investigated with the goal of determining if irradiation of this dimer generates a powerful reducing agent, presumably a 19-electron species. In general, the photochemistry of the W2(CO)102- complex is comparable to that of other metal-metal-bonded carbonyl dimers. Irradiation into the low-energy tail of the d π → σ* electronic transition of the W2(CO)102- complex led to W-W bond homolysis. The resulting 17-electron W(CO)5- radicals could be trapped with suitable ligands such as 4-cyanopyridine to give 19-electron adducts . (See ref 3 for an important definition of the phrase 19-electron adduct .) Evidence is presented that the ligands PPh3 and PBu3 also react with photogenerated W(CO)5- to form adducts: W(CO)5- + PR3 → W(CO)5PR3-. These adducts are powerful reducing agents, and they were used to reduce CO2 to formate and CO. The only organometallic product formed in the reaction was W(CO)5PPh3, the oxidized form of the 19-electron complex. In a similar manner, Mn2(CO)10 was reduced to Mn(CO)5-, Cp2Co+ to Cp2Co, benzophenone to the radical anion, and methylviologen (MV2+) to MV+. Alternative reduction mechanisms involving the W(CO)5- radical, W(CO)52-, or HW2(CO)10- as reductants were shown not to be operating. Nineteen-electron complexes generated by irradiation of Cp2Mo2(CO)6 proved incapable of reducing CO2.
KINETISCHE UND MECHANISTISCHE UNTERSUCHUNGEN VON UEBERGANGSMETALL-KOMPLEX-REAKTIONEN XXII. KONKURRENZ ZWISCHEN DISSOZIATIVEM UND ASSOZIATIVEM MECHANISMUS BEI DER REAKTION VON PENTACARBONYL(DIPHENYLCARBEN)WOLFRAM MIT NITRILEN
Fischer, Helmut,Zeuner, Siegfried
, p. 63 - 76 (2007/10/02)
The reaction of pentacarbonyl(diphenylcarbene)tungsten, (CO)5W=CPh2 (I), with organyl nitriles, (II) (R = C6H4NMe2-p (a), C6H4OMe-p (b), Ph (c), Me (d), But (e)), yields the insertion product (CO)5W (III), the nitrile complexes (IV) and (V) and diphenyl ketene, Ph2C=C=O.The product distribution depends on the type and the concentration of the organyl nitrile II.At constant temperature, the yield of III increases and that of IV as well as that of diphenyl ketene decreases with increasing concentration of II and in the order IId, IIc, IIb, IIa.When I reacts with IIb in the presence of 13CO, 13CO is incorporated almost exclusively into IVb.At 50.6 deg C in 1,1,2-trichloroethane, the reaction of I with IIa-d follows an additive rate law: -d/dt = k1 + k2.The rate constant k1 is independent of the type of II and agrees well with the rate constant for the dissociative thermolysis of I in 1,1,2-trichloroethane, however, k2 clearly increases in the series IId-a.A reaction scheme is proposed consisting of an associative pathway (giving III) and a dissociative pathway leading to the compounds IV, V and diphenyl ketene.
