69446-48-6Relevant academic research and scientific papers
Reactivity Study of Pyridyl-Substituted 1-Metalla-2,5-diaza-cyclopenta-2,4-dienes of Group 4 Metallocenes
Becker, Lisanne,Rei?, Fabian,Altenburger, Kai,Spannenberg, Anke,Arndt, Perdita,Jiao, Haijun,Rosenthal, Uwe
, p. 10826 - 10838 (2016/07/27)
In this work the reactivity of 1-metalla-2,5-diaza-cyclopenta-2,4-dienes of group 4 metallocenes, especially of the pyridyl-substituted examples, towards small molecules is investigated. The addition of H2, CO2, Ph?C≡N, 2-py?C≡N, 1,3-dicyanobenzene or 2,6-dicyanopyridine results in exchange reactions, which are accompanied by the elimination of a nitrile. For CO2, a coordination to the five-membered cycle occurs in case of Cp*2Zr(N=C(2-py)?C(2-py)=N). A 1,4-diaza-buta-1,3-diene complex is formed by H-transfer in the conversion of the analogous titanocene compound with CH3?C≡N, PhCH2?C≡N or acetone. For CH3?C≡N a coupling product of three acetonitrile molecules is established additionally. In order to split off the metallocene from the coupled nitriles, we examined reactions with HCl, PhPCl2, PhPSCl2and SOCl2. In the last case, the respective thiadiazole oxides and the metallocene dichlorides were obtained. A subsequent reaction produced thiadiazoles.
Reductive silylation of Cp?UO2(MesPDIMe) promoted by Lewis bases
Kiernicki,Harwood,Fanwick,Bart
, p. 3111 - 3119 (2016/02/20)
Functionalization of the uranyl moiety (UO22+) in Cp?UO2(MesPDIMe) (1-PDI) (MesPDIMe = 2,6-((Mes)NCMe)2C5H3N; Mes = 2,4,6-triphenylmethyl), which bears a reduced, monoanionic pyridine(diimine) ligand, is reported. Silylating reagents, R3Si-X (R = Me, X = Cl, I, OTf, SPh; R = Ph, X = Cl), effectively add across the strong OUO bonds in the presence of the Lewis base, OPPh3, generating products of the form (R3SiO)2UX2(OPPh3)2 (R = Me, X = I (2-OPPh3), Cl (3-OPPh3), SPh (5-OPPh3), OTf (6-OPPh3); R = Ph, X = Cl (4-OPPh3)). During this transformation, reduction to uranium(iv) occurs with loss of (Cp?)2 and MesPDIMe, each of which acts as a one-electron source. In the reaction, the Lewis base serves to activate the silyl halide, generating a more electrophilic silyl group, as determined by 29Si NMR spectroscopy, that undergoes facile transfer to the oxo groups. Complete U-O bond scission was accomplished by treating the uranium(iv) disiloxide compounds with additional silylating reagent, forming the family (Ph3PO)2UX4. All compounds were characterized by 1H NMR, infrared, and electronic absorption spectroscopies. X-ray crystallographic characterization was used to elucidate the structures of 2-OPPh3, 4-OPPh3, 5-OPPh3, and 6-OPPh3.
Synthesis and characterization of cyclopentadienylgallium amide compounds as potential single source precursors to GaN
Perrotin,Kennon, Bretni S.,Twamley, Brendan,Miller, Joel S.,Shapiro, Pamela J.
, p. 216 - 222 (2015/02/19)
The synthesis, spectroscopic characterization, and single crystal X-ray structures of [(η5-C5Me4H)2Ga(μ2-NH2)] (1), [(η5-C5Me5)2Ga(μ2-
(Pentamethylcyclopentadienyl)indium(I) and -indium(III) compounds. Syntheses, reactivities, and X-ray diffraction and electron diffraction studies of In(C5Me5)
Beachley Jr.,Blom, Richard,Churchill, Melvyn Rowen,Faegri Jr., Knut,Fettinger, James C.,Pazik,Victoriano
, p. 346 - 356 (2008/10/08)
The golden yellow compound In(C5Me5) has been prepared in 62% yield from InCl and Li(C5Me5) in diethyl ether and fully characterized according to its physical and solubility properties, its reaction with dilute aqueous HCl, a cryoscopic molecular weight study in cyclohexane, IR and 1H NMR spectroscopic properties, a single-crystal X-ray diffraction study, and a gas-phase electron diffraction study. The other products of this reaction have been identified as In(C5Me5)2Cl, indium metal, and (C5Me5)2 in 5.0, 21, and 2.5% yields, respectively. The identity of the yellow indium(III) product In(C5Me5)2Cl was confirmed by its independent synthesis from InCl3 and Li(C5Me5) in a 1:2 mol ratio and full characterization. The orange-yellow compound In(C5Me5)Cl2 has also been synthesized from InCl3 and Li(C5Me5) in a 1:1 mol ratio in order to distinguish it from In(C5Me5)2Cl. However, the attempted preparation of In(C5Me5)3 from InCl3 and either Li(C5Me5) or Na(C5Me5) was unsuccessful. A noteworthy observation of the chemical properties of the (pentamethylcyclopentadienyl)indium(I) and -indium(III) compounds was their decomposition in benzene solution to form (C5Me5)2 and other products. Additional studies of prepurified In(C5Me5) confirmed decomposition in THF and pyridine but demonstrated its stability in cyclohexane. The compound In(η5-C5Me5) crystallizes in the rhombohedral space group R3 (C3i2; No. 148) with unit cell parameters (hexagonal setting) a = 20.182 (4) A?, c = 13.436 (3) A?, V = 4739 12) A?3, and Z = 18. Single-crystal X-ray diffraction data (Mo Kα, 2θ = 4.5-50.0°) were collected with a Syntex P21 automated four-circle diffractometer; the structure was solved and refinement converged with RF = 3.6%. and RwF = 3.3% for all 1870 symmetry-independent data (none rejected) and RF = 2.5% and RwF = 2.9% for those 1444 reflections with |Fo| > 6σ(|Fo|). The η5-C5Me5 ligand is symmetrically bound to indium with In-C = 2.581 (4)-2.613 (4) A? (average = 2.595 A?) and In?centroid = 2.302 A?. The In(η5-C5Me5) units are arranged about centers of 3 (S6) symmetry, with indium atoms on the interior and η5-C5Me5 units on the exterior of hexameric units in which In-In distances are 3.942 (1)-3.963 (1) A?. The centroid → indium vectors do not point toward the center of the hexaindium cluster as in other main-group clusters. The molecular structure of In(C5Me5) in the gas phase consists of discrete monomeric units with the indium(I) atom being situated 2.288 A? above the ring centroid. Ab initio calculations were carried out on In(C5H5) and In(C5Me5) in an attempt to understand the effects of methyl groups on the bonding between indium(I) and the cyclopentadienyl ring.
