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181.
Complexes of Vanadium and Titanium with Salicylaldehyde benzoylhydrazone and 2-(2′-Hydroxyphenyl)-8-quinolinol. Crystal Structure of μ-Oxo-bis[oxo{2-(2′-hydroxyphenyl)-8-quinolinato(2-)}-vanadium(V)] . By reaction of titanium(IV)-isopropoxide and bis(acetylacetonato)-oxovanadium(IV) with salicylaldehyde benzoylhydrazone and 2-(2′hydroxyphenyl)-8-quinolinol, respectively, the metal complexes of the tridentate diacidic ligands were synthesized and characterized mass spectrometrically. The mass spectra of the titanium compounds correspond to the expected bisligand complexes whereas several species are demonstrable in the case of vanadium. Crystals of μ-oxo-bis[oxo{2-(2′-hydroxyphenyl)-8-quinolinolato(2-)}-vanadium(V)] were isolated and characterized by X-ray structural analysis. The complex exhibits C2 symmetry, accordingly the μ2-oxygen atom is situated on the 4 axis. The VOV bridge is angular with the unusually small bond angle of 107.3°. The coordination polyhedron is distorted octahedral. The compound additionally contains one molecule of chloroform per formula unit which is disordered in two positions. Crystallographic data see “Inhaltsübersicht”. 相似文献
182.
The reactions of CpRu(dppf)Cl (1) with the sulfur-containing ligands, thiophenol HSPh, 2-mercaptopyridine C5H4N(SH), thiourea SC(NH2)2, vinylene trithiocarbonate SCS(CH)2S and ethylene trithiocarbonate SCS(CH2)2S, yielded chloro-substituted derivatives, viz. the mono-ruthenium(II) complexes CpRu(dppf)(SPh) (2), [CpRu(dppf)(SC5H4NH)]BPh4 (3)BPh4, [CpRu(dppf)(SC(NH2)2]PF6 (4)PF6, [CpRu(dppf)(SCS(CH)2S)]Cl (5)Cl and [CpRu(dppf)(SCS(CH2)2S)]Cl (6)Cl, respectively. Treatment of 1 with AuCl(SMe2) in the presence of NH4PF6 gave [(CpRu(dppf)(SMe2)]PF6 (7)PF6. The reaction of 1 or 6 with SnCl2 resulted in cleavage of chloro and dithiocarbonate ligands, respectively, to give CpRu(dppf)SnCl3 (8). All complexes were spectroscopically characterized and the structures of 2 and cationic complexes 4-7 were determined by single-crystal diffraction analyses. 相似文献
183.
Sellmann D Hille A Rösler A Heinemann FW Moll M Brehm G Schneider S Reiher M Hess BA Bauer W 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(4):819-830
In the quest for low-molecular-weight metal sulfur complexes that bind nitrogenase-relevant small molecules and can serve as model complexes for nitrogenase, compounds with the [Ru(PiPr(3))('N(2)Me(2)S(2)')] fragment were found ('N(2)Me(2)S(2)'(2-)=1,2-ethanediamine-N,N'-dimethyl-N,N'-bis(2-benzenethiolate)(2-)). This fragment enabled the synthesis of a first series of chiral metal sulfur complexes, [Ru(L)(PiPr(3))('N(2)Me(2)S(2)')] with L=N(2), N(2)H(2), N(2)H(4), and NH(3), that meet the biological constraint of forming under mild conditions. The reaction of [Ru(NCCH(3))(PiPr(3))('N(2)Me(2)S(2)')] (1) with NH(3) gave the ammonia complex [Ru(NH(3))(PiPr(3))('N(2)Me(2)S(2)')] (4), which readily exchanged NH(3) for N(2) to yield the mononuclear dinitrogen complex [Ru(N(2))(PiPr(3))('N(2)Me(2)S(2)')] (2) in almost quantitative yield. Complex 2, obtained by this new efficient synthesis, was the starting material for the synthesis of dinuclear (R,R)- and (S,S)-[micro-N(2)[Ru(PiPr(3))('N(2)Me(2)S(2)')](2)] ((R,R)-/(S,S)-3). (Both 2 and 3 have been reported previously.) The as-yet inexplicable behavior of complex 3 to form also the R,S isomer in solution has been revealed by DFT calculations and (2)D NMR spectroscopy studies. The reaction of 1 or 2 with anhydrous hydrazine yielded the hydrazine complex [Ru(N(2)H(4))(PiPr(3))('N(2)Me(2)S(2)')] (6), which is a highly reactive intermediate. Disproportionation of 6 resulted in the formation of mononuclear diazene complexes, the ammonia complex 4, and finally the dinuclear diazene complex [micro-N(2)H(2)[Ru(PiPr(3))('N(2)Me(2)S(2)')](2)] (5). Dinuclear complex 5 could also be obtained directly in an independent synthesis from 1 and N(2)H(2), which was generated in situ by acidolysis of K(2)N(2)(CO(2))(2). Treatment of 6 with CH(2)Cl(2), however, formed a chloromethylated diazene species [[Ru(PiPr(3))('N(2)Me(2)S(2)')]-micro-N(2)H(2)[Ru(Cl)('N(2)Me(2)S(2)CH(2)Cl')]] (9) ('N(2)Me(2)S(2)CH(2)Cl'(2-) =1,2-ethanediamine-N,N'-dimethyl-N-(2-benzenethiolate)(1-)-N'-(2-benzenechloromethylthioether)(1-)]. The molecular structures of 4, 5, and 9 were determined by X-ray crystal structure analysis, and the labile N(2)H(4) complex 6 was characterized by NMR spectroscopy. 相似文献
184.
CHENG Peng YAN Shi-Ping LIAO Dai-Zheng BAI Ling-Jun JIANG Zong-Hui WANG Geng-LinDepartment of Chemistry Nankai Uviversity Tianjin China 《中国化学》1994,12(4):314-320
The syntheses and magnetic properties are reported for a series of copper(Ⅱ) complexes prepared from a pentadentate binucleating ligand 2,6-diformyl-4-methylphenol di(benzoyl-hydrazone) (H3L). These complexes incorporate different exogenous ions (X-) into a bridging position to form copper(Ⅱ) binuclear complexes of the formula [Cu2(H2L)X]2+, where X-= Br-(1), Cl-(2), HO-(3), C2H5O-(4) and C3H3N2- (5). The complexes have been characterized with variable temperature magnetic susceptibility (4.2-300 K) and the observed data were fit to those from a modified Bleaney-Bowers equation by least-squares method, giving the exchange integral 2J = -6.2 cm-1 for 1, -76.4 cm-1 for 2, -241.9 cm-1 for 3, -231.1 cm-1 for 4 and -343.8 cm-1 for 5. This suggested that there is an antiferromagnetic interaction between the Cu(Ⅱ) ions and the sequence of the effect of some exogenous bridging ligands on magnetic coupling is corresponding to that in spectrochemical series. 相似文献
185.
Bruno Therrien Ludovic Vieille-Petit Petr Štěpni?ka Georg Süss-Fink 《Journal of organometallic chemistry》2004,689(15):2456-2463
A series of arene-ruthenium complexes of the general formula [RuCl2{η6-C6H5(CH2)2R}L] with R=OH, CH2OH, OC(O)Fc, CH2OC(O)Fc (Fc=ferrocenyl) and L=PPh3, (diphenylphosphino)ferrocene, or bridging 1,1′-bis(diphenylphosphino)ferrocene, have been synthesized. Two synthetic pathways have been used for these ferrocene-modified arene-ruthenium complexes: (a) esterification of ferrocene carboxylic acid with 2-(cyclohexa-1,4-dienyl)ethanol, followed by condensation with RuCl3 · nH2O to afford [RuCl2{η6-C6H5(CH2)2OC(O)Fc}]2, and (b) esterification between ferrocene carboxylic acid and [RuCl2{η6-C6H5(CH2)3OH}L] to give [RuCl2{η6-C6H5(CH2)3OC(O)Fc}L]. All new compounds have been characterized by NMR and IR spectroscopy as well as by mass spectrometry. The single-crystal X-ray structure analysis of [RuCl2{η6-C6H5(CH2)3OH}(PPh3)] shows that the presence of a CH2CH2CH2OH side-arm allows [RuCl2{η6-C6H5(CH2)3OH}(PPh3)] to form an intramolecular hydrogen bond with a chlorine atom. The electrochemical behavior of selected representative compounds has been studied. Complexes with ferrocenylated side arms display the expected cyclic voltammograms, two independent reversible one-electron waves of the Ru(II)/Ru(III) and Fe(II)/Fe(III) redox couples. Introduction of a ferrocenylphosphine onto the ruthenium is reflected by an additonal reversible, one-electron wave due to ferrocene/ferrocenium system which is, however, coupled with the Ru(II)/Ru(III) redox system. 相似文献
186.
Koen Vandyck 《Tetrahedron letters》2005,46(1):75-78
2,3,6,7-Tetrahydro-as-indacene-1,8-dione 4 was prepared in 4 steps starting from 2-methyl-furan by modification of a literature procedure. Appliance of Noyori’s asymmetric transfer hydrogenation, resulted in (1S,8S)-1,2,3,6,7,8-hexahydro-as-indacene-1,8-diol 5 in high yield (81%) and excellent enantioselectivity (>99% ee) or (8S)-8-hydroxy-3,6,7,8-tetrahydro-2H-as-indacen-1-one 6 in moderate yield (58%) and equally high enantioselectivity (98.5% ee), depending on the conditions. The asymmetric reduction was expected to yield the (S)-alcohols using the (S,S)-Ts-DPEN ligand, which was confirmed by the appliance of the exciton chirality method on the corresponding bis(p-dimethylamino)benzoate 7. 相似文献
187.
From a range of preparative methods, three geometric isomers of bis(diphenylarsino)methane‐dichloroplatinum(II) have been isolated, viz. cis‐PtCl2(dpam), trans, trans‐Pt2Cl4(dpam)2 and cis, trans‐Pt2Cl4(dpam)2. Their structures were determined by single‐crystal X‐ray diffraction. 相似文献
188.
Abarca A Galakhov MV Gracia J Martín A Mena M Poblet JM Sarasa JP Yélamos C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(10):2337-2346
Treatment of [[Ti(eta(5)-C(5)Me(5))(micro-NH)](3)(micro(3)-N)] (1) with the imido complexes [Ti(NAr)Cl(2)(py)(3)] (Ar=2,4,6-C(6)H(2)Me(3)) and [Ti(NtBu)Cl(2)(py)(3)] in toluene affords the single azatitanocubanes [[Cl(2)(ArN)Ti]( micro(3)-NH)(3)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]].(C(7)H(8)) (2.C(7)H(8)) and [[Cl(2)Ti](micro(3)-N)(2)(micro(3)-NH)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]] (3), respectively. Similar reactions of complex 1 with the niobium and tantalum imido derivatives [[M(NtBu)(NHtBu)Cl(2)(NH(2)tBu)](2)] (M=Nb, Ta) in toluene give the single azaheterometallocubanes [[Cl(2)(tBuN)M](micro(3)-N)(micro(3)-NH)(2)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]] (M=Nb (4), Ta (5)), both complexes react with 2,4,6-trimethylaniline to yield the analogous species [[Cl(2)(ArN)M](micro(3)-N)(micro(3)-NH)(2)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]].(C(7)H(8)) (Ar=2,4,6-C(6)H(2)Me(3), M=Nb (6.C(7)H(8)), Ta (7.C(7)H(8))). Also the azaheterodicubanes [M[micro(3)-N)(2)(micro(3)-NH)](2)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)](2)].2C(7)H(8) [M=Ti (8.2C(7)H(8)), Zr (9.2C(7)H(8))], and [M[(micro(3)-N)(5)(micro(3)-NH)][Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)](2)].2 C(7)H(8) (Nb (10.2C(7)H(8)), Ta (11.2C(7)H(8))) were prepared from 1 and the homoleptic dimethylamido complex [M(NMe(2))(x)] (x=4, M=Ti, Zr; x=5, M=Nb, Ta) in toluene at 150 degrees C. X-ray crystal structure determinations were performed for 6 and 10, which revealed a cube- and double-cube-type core, respectively. For complexes 2 and 4-7 we observed and studied by DNMR a rotation or trigonal-twist of the organometallic ligands [[Ti(eta(5)-C(5)Me(5))(micro-NH)](3)(micro(3)-N)] (1) and [(micro(3)-N)(micro(3)-NH)(2)[Ti(3)(eta(5)-C(5)Me(5))(3)(micro(3)-N)]](1-). Density functional theory calculations were carried out on model complexes of 2, 3, and 8 to establish and understand their structures. 相似文献
189.
The ligands [Ph2P(O)NP(E)Ph2]− (E=S I; E=Se II) can readily be complexed to a range of palladium(II) starting materials affording new six-membered Pd–O–P–N–P–E palladacycles. Hence ligand substitution reaction of the chloride complexes [PdCl2(bipy)] (bipy=2,2′-bipyridine), [{Pd(μ-Cl)(L–L)}2] (HL–L=C9H13N or C12H13N), [{Pd(μ-Cl)Cl(PMe2Ph)}2] or [PdCl2(PR3)2] [PR3=PPh3; 2PR3=Ph2PCH2CH2PPh2or cis-Ph2PCH=CHPPh2] with either I (or II) in thf or CH3OH gave [Pd{Ph2P(O)NP(E)Ph2-O,E}(bipy)]PF6, [Pd{Ph2P(O)NP(E)Ph2-O,E}(L–L)], [Pd{Ph2P(O)NP(E)Ph2-O,E}Cl(PMe2Ph)] or [Pd{Ph2P(O)NP(E)Ph2-O,E} (PR3)2]PF6 in good yields. All compounds described have been characterised by a combination of multinuclear NMR [31 P{1 H} and 1 H] and IR spectroscopy and microanalysis. The molecular structures of five complexes containing the selenium ligand II have been determined by single-crystal X-ray crystallography. Three different ring conformations were observed, a pseudo-butterfly, hinge and in the case of all three PR3 complexes, pseudo-boat conformations. Within the Pd–O–P–N–P–Se rings there is evidence for π-electron delocalisation. 相似文献
190.
Luis Adrio Gemma Alberdi Adriana Amoedo Darío Lata Alberto Fernndez Javier Martínez M. Teresa Pereira Jos M. Vila 《无机化学与普通化学杂志》2005,631(11):2197-2203
Reaction of the thiosemicarbazone ligands C4H4NC(H)=NN(H)C(S)NHR (R = Me, a ; Et, b ) with Li2[PdCl4] gave the dinuclear complexes [Pd{C4H4NC(H)=NNC(S)NHR}(μ‐Cl)]2 (R = Me, 1a ; Et, 1b ) with a central Pd2Cl2 core and with deprotonation of the thiosemicarbazones at the hydrazinic nitrogen atom. Treatment of 1a and 1b with triphenylphosphine gave the mononuclear compounds [Pd{C4H4C(H)=NNC(S)NHR}(Cl)(PPh3)] (R = Me, 2a ; Et, 2b ), whereas reaction of 1a and 1b with tertiary diphosphines gave mono‐ and dinuclear compounds, as appropriate, with the corresponding diphosphine acting as a monodentate ( 6b ), chelating ( 3a ) and bridging ligand ( 4a, 5a , 4b, 5b ). Treatment of 1a and 1b with (Ph2PCH2CH2PPh2)W(CO)5 gave the new heterobimetallic complexes 7a and 7b . The crystal structures of complexes 3a and 4a are described. 相似文献