25734-54-7Relevant articles and documents
Synthesis, characterization, and reactivity of a rhenium complex with a corannulene-based ligand
Chin, Robert M.,Baird, Benjamin,Jarosh, Michael,Rassman, Shane,Barry, Brian,Jones, William D.
, p. 4829 - 4832 (2003)
A new rhenium carbonyl complex, exo-(η5-C20H17)Re(CO)3 (3), containing a corannulene-derived ligand has been synthesized in 12% yield. The X-ray structure determination of 3 shows that the rhenium center is bound to the exo face of the bowl-shaped ligand. The reaction of 3 with PPh3 in benzene at 70°C produces trans,mer-Re(H)(PPh3)2(CO)3 and C20H16 (4), a bowl-shaped dibenzofulvene type molecule. The reaction of 3 with PPh3 proceeds via an η5-η3-η1 ring slip followed by a β-hydride elimination.
Preparations, structures, and electrochemical studies of aryldiazene complexes of rhenium: Syntheses of the first heterobinuclear and heterotrinuclear derivatives with bis(diazene) or bis(diazenido) bridging ligands
Albertin, Gabriele,Antoniutti, Stefano,Bacchi, Alessia,Ballico, Giovanni B.,Bordignon, Emilio,Pelizzi, Giancarlo,Ranieri, Maria,Ugo, Paolo
, p. 3265 - 3279 (2008/10/08)
The mono- and binuclear aryldiazene complexes [Re(C6H5N=NH)(CO)(5-n)P(n)]BY4 (1-5) and [{Re(CO)(5-n)P(n)}2-(μ-HN=NAr-ArN=NH)](BY4)2 (6-12) [P = P(OEt)3, PPh(OEt)2, PPh2OEt; n = 1-4; Ar-Ar = 4,4'-C6H4-C6H4, 4,4'-(2-CH3)C6H3-C6H3(2-CH3), 4,4'-C6H4-CH2-C6H4; Y = F, Ph) were prepared by reacting the hydride species ReH(CO)(5-n)P(n) with the appropriate mono- and bis(aryldiazonium) cations. These compounds, as well as other prepared compounds, were characterized spectroscopically (IR; 1H, 31P, 13C, and 15N NMR data), and 1a was also characterized by an X-ray crystal structure determination. [Re(C6H5N=NH)(CO){P(OEt)3}4]BPh4 (1a) crystallizes in space group P1 with a = 15.380(5) A, b = 13.037(5) A, c = 16.649(5) A, α = 90.33(5)°, β = 91.2(1)°, γ = 89.71(9)°, and Z = 2. The 'diazene-diazonium' complexes [M(CO)3P2(HN=NAr-ArN≡N)]-(BF4)2 (13-15, 17) [M = Re, Mn; P = PPh2OEt, PPh2OMe, PPh3; Ar-Ar = 4,4'-C6H4-C6H4, 4,4'-C6H4-CH2-C6H4] and [Re(CO)4(PPh2OEt)(4,4'-HN=NC6H4-C6H4N≡N)](BF4)2 (16b) were synthesized by allowing the hydrides MH(CO)3P2 or ReH(CO)4P to react with equimolar amounts of bis(aryldiazonium) cations under appropriate conditions. Reactions of diazene-diazonium complexes 13-17 with the metal hydrides M2H2P'4 and M2'H(CO)(5-n)P''(n) afforded the heterobinuclear bis(aryldiazene) derivatives [M1(CO)3P2(μ-HN=NAr-ArN=NH)M2HP'4](BPh4)2 (ReFe, ReRu, ReOs, MnRu, MnOs) and [M1(CO)3P2(μ-HN=NAr-ArN=NH)M2'-(CO)(5-n)P''(n)](BPh4)2 (ReMn, MnRe) [M1 = Re, Mn; M2 = Fe, Ru, Os; M2' = Mn, Re; P = PPh2OEt, PPh2OMe; P', P'' = P(OEt)3, PPh(OEt)2; Ar-Ar = 4,4'-C6H4-C6H4, 4,4'-C6H4-CH2-C6H4; n = 1, 2]. The heterotrinuclear complexes [Re(CO)3(PPh2OEt)2(μ-4,4'-HN=NC6H4-C6H4N=NH)M{P(OEt)3}4(μ-4,4'-H N=NC6H4-C6H4N=NH)Mn(CO)3(PPh2OEt)2](BPh4)4 (M = Ru, Os) (ReRuMn, ReOsMn) were obtained by reacting the heterobinuclear complexes ReRu and ReOs with the appropriate diazene-diazonium cations. The heterobinuclear complex with a bis(aryldiazenido) bridging ligand [Mn(CO)2(PPh2OEt)2(μ-4,4'-N2C6H4-C6H4N2)Fe{P(OEt)3}4]BPh4 (MnFe) was prepared by deprotonating the bis(aryldiazene) compound [Mn(CO)3(PPh2OEt)2(μ-4,4'-HN=NC6H4-C6H4N=NH)Fe(4-CH3C6H4CN){P(OEt )3}4](BPh4)3. Finally, the binuclear compound [Re(CO)3(PPh2OEt)2(μ-4,4'-HN=NC6H4-C6H4N2)Fe(CO)2{P(OPh)3}2](BP h4)2 (ReFe) containing a diazene-diazenido bridging ligand was prepared by reacting [Re(CO)3(PPh2OEt)2(4,4'-HN=NC6H4-C6H4N≡N)]+ with the FeH2(CO)2{P(OPh)3}2 hydride derivative. The electrochemical reduction of mono- and binuclear aryldiazene complexes of both rhenium (1-12) and the manganese, as well as heterobinuclear ReRu and MnRu complexes, was studied by means of cyclic voltammetry and digital simulation techniques. The electrochemical oxidation of the mono- and binuclear aryldiazenido compounds Mn(C6H5N2)(CO)2P2 and {Mn(CO)2P2}2(μ-4,4'-N2C6H4-C6H4N2) (P = PPh2OEt) was also examined. Electrochemical data show that, for binuclear compounds, the diazene bridging unit allows delocalization of electrons between the two different redox centers of the same molecule, whereas the two metal centers behave independently in the presence of the diazenido bridging unit.
Reactions of coordinated diazene in rhenium and tungsten complexes. Deprotonation of ligated NH=NH and subsequent H-migration to carbonyl ligands to give metal formyls
Cheng, Tan-Yun,Peters, Jonas C.,Hillhouse, Gregory L.
, p. 204 - 207 (2007/10/02)
The tungsten diazene complex [trans,trans- W(NH=NH)(CO)2(NO)(PPh3)2+][SO3CF3-] (1) reacts with NH2R (R = H, CH3, NH2) to give trans,trans-W(η1-OSO2CF3)(CO)2(NO)(PPh3)2 (2), trans,trans-W(H)(CO)2(NO)(PPh3)2 (3), and [trans,trans- W(NH2NH2)(CO)2(NO)(PPh3)2+][SO3CF3-] (4). If the reaction of NH2R with 1 is monitored at -78 °C, intermediates in the formation of 3 can be observed, which have been characterized as the neutral 6-coordinate formyl complexes trans-W(CH=O)(CO)(NO)(NH2R)(PPh3)2 (5a, R = H; 5b, R = CH3; 5c, R = NH2) on the basis of multinuclear (1H, 13C, 31P) NMR spectroscopy and 2H and 13C labeling experiments. The noncoordinating Bronsted base NaN(SiMe3)2 reacts with 1 to give 3 in 47% isolated yield, but because of the absence of a coordinating Lewis base, no formyl intermediate was observed. A reaction mechanism for the formation of hydride 3 is proposed involving (i) deprotonation of the diazene ligand in 1 by NH2R, (ii) H- migration from nitrogen to a carbonyl ligand to give the formyl complexes 5, and (iii) H-migration from the formyl ligand to the metal to give the neutral hydride product 3. The isoelectronic rhenium diazene complex [trans,mer- Re(NH=NH)(CO)3(PPh3)2+][SO3-CF3-] (9) has been prepared and shown to undergo a similar reaction with NH2CH3 to give trans,mer- Re(H)(CO)3(PPh3)2 (6) in 80% yield.
