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1.
Christian Slugovc Kurt Mereiter Swiatoslaw Trofimenko Ernesto Carmona 《Helvetica chimica acta》2001,84(10):2868-2883
A series of pyrazole‐substituted [hydrotris(1H‐pyrazolato‐κN1)borato(1−)]iridium complexes of the general composition [Ir(Tpx)(olefin)2] (Tpx=TpPh and TpTh) and their capability to activate C−H bonds is presented. As a test reaction, the double C−H activation of cyclic‐ether substrates leading to the corresponding Fischer carbene complexes was chosen. Under the reaction conditions employed, the parent compound [Ir(TpPh)(ethene)2] was not isolable; instead, (OC‐6‐25)‐[Ir(TpPhκCPh,κ3N,N′,N″)(ethyl)(η2‐ethene)] ( 1 ) was formed diastereoselectively. Upon further heating, 1 could be converted exclusively to (OC‐6‐24)‐[Ir(TpPhκ2CPh,CPh,κ3N,N′,N″)(η2‐ethene)] ( 2 ). Complex 1 , but not 2 , reacted with THF to give (OC‐6‐35)‐[Ir(TpPhκ3N,N′,N″)H(dihydrofuran‐2(3H)‐ylidene)] ( 3 ), a cyclic Fischer carbene formed by double C−H activation of THF. Accordingly, complexes of the general formula [Ir(Tpx)(butadiene)] (see 4 – 6 ; butadiene=buta‐1,3‐diene, 2‐methylbuta‐1,3‐diene (isoprene), 2,3‐dimethylbuta‐1,3‐diene) reacted with THF to yield 3 or the related derivative 9 . The reaction rate was strongly dependent on the steric demand of the butadiene ligand and the nature of the substituent at the 3‐position of the pyrazole rings. 相似文献
2.
Ansa‐Complexes of [Mn(η5‐C5H5)(η6‐C6H6)]: Preparation,Characterization, and Reactivity of [n]Manganoarenophanes (n=1, 2, 3)
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Prof. Dr. Holger Braunschweig Dr. Alexander Damme Dr. Klaus Dück Dr. Marco Fuß Dr. Christian Hörl Dr. Thomas Kramer Dr. Ivo Krummenacher Dr. Thomas Kupfer Valerie Paprocki Christoph Schneider 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(42):14797-14803
We report the synthesis of [n]manganoarenophanes (n=1, 2) featuring boron, silicon, germanium, and tin as ansa‐bridging elements. Their preparation was achieved by salt‐elimination reactions of the dilithiated precursor [Mn(η5‐C5H4Li)(η6‐C6H5Li)]?pmdta (pmdta=N,N,N′,N′,N′′‐pentamethyldiethylenetriamine) with corresponding element dichlorides. Besides characterization by multinuclear NMR spectroscopy and elemental analysis, the identity of two single‐atom‐bridged derivatives, [Mn(η5‐C5H4)(η6‐C6H5)SntBu2] and [Mn(η5‐C5H4)(η6‐C6H5)SiPh2], could also be determined by X‐ray structural analysis. We investigated for the first time the reactivity of these ansa‐cyclopentadienyl–benzene manganese compounds. The reaction of the distannyl‐bridged complex [Mn(η5‐C5H4)(η6‐C6H5)Sn2tBu4] with elemental sulfur was shown to proceed through the expected oxidative addition of the Sn?Sn bond to give a triatomic ansa‐bridge. The investigation of the ring‐opening polymerization (ROP) capability of [Mn(η5‐C5H4)(η6‐C6H5)SntBu2] with [Pt(PEt3)3] showed that an unexpected, unselective insertion into the Cipso?Sn bonds of [Mn(η5‐C5H4)(η6‐C6H5)SntBu2] had occurred. 相似文献
3.
Reaction of potassium salt of N‐aryliminopyrrole ligand [2‐(2, 6‐iPr2C6H3N=CH)–C4H3NK] ( 1 ) with samarium tris‐boro‐hydride [Sm(BH4)3(THF)3] gave a samarium ate complex [η2‐{2‐(2, 6‐iPr2C6H3N=CH)–C4H3N}3Sm(η1‐BH4){K(THF)6] ( 2 ); whereas similar treatment with erbium borohydride [Er(BH4)3(THF)3] afforded the mono(iminopyrrolyl) complex [η2‐{2‐(2, 6‐iPr2C6H3N=CH)–C4H3N}Er(η3‐BH4)2(THF)2] ( 3 ). In the solid‐state structures, the samarium complex 2 shows a rarely observed η1 and the erbium complex 3 shows a usual η3 coordination mode of the borohydrido ligand. 相似文献
4.
D. M. Roitershtein M. E. Minyaev A. A. Mikhailyuk K. A. Lyssenko P. A. Belyakov M. Yu. Antipin 《Russian Chemical Bulletin》2007,56(10):1978-1985
The reaction of LuCl3(THF)3 with Na(1,3-Ph2C5H3) followed by the in situ reaction with Na2[Ph4C2] produced (1,3-Ph2C5H3)Lu(Ph4C2)(THF) (1). The structure of 1 was established by X-ray diffraction. In the crystal structure of 1, the bis-allyl η6-coordination of the tetraphenylethylene dianion to the lutetium cation was observed. The structures of (1,3-Ph2C5H3)LuCl2(THF)3 and (C5H5)LuCl2(THF)3 were determined by X-ray diffraction.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1912–1918, October, 2007. 相似文献
5.
《Acta Crystallographica. Section C, Structural Chemistry》2017,73(5):420-423
Only a few cyclooctatetraene dianion (COT) π‐complexes of lanthanides have been crystallographically characterized. This first single‐crystal X‐ray diffraction characterization of a scandium(III) COT chloride complex, namely di‐μ‐chlorido‐bis[(η8‐cyclooctatetraene)(tetrahydrofuran‐κO )scandium(III)], [Sc2(C8H8)2Cl2(C4H8O)2] or [Sc(COT)Cl(THF)]2 (THF is tetrahydrofuran), (1), reveals a dimeric molecular structure with symmetric chloride bridges [average Sc—Cl = 2.5972 (7) Å] and a η8‐bound COT ligand. The COT ring is planar, with an average C—C bond length of 1.399 (3) Å. The Sc—C bond lengths range from 2.417 (2) to 2.438 (2) Å [average 2.427 (2) Å]. Direct comparison of (1) with the known lanthanide (Ln) analogues (La, Ce, Pr, Nd, and Sm) illustrates the effect of metal‐ion (M ) size on molecular structure. Overall, the M —Cl, M —O, and M —C bond lengths in (1) are the shortest in the series. In addition, only one THF molecule completes the coordination environment of the small ScIII ion, in contrast to the previously reported dinuclear Ln–COT–Cl complexes, which all have two bound THF molecules per metal atom. 相似文献
6.
Thorsten Morawitz Michael Bolte Hans‐Wolfram Lerner Matthias Wagner 《无机化学与普通化学杂志》2008,634(9):1570-1574
The synthesis and full characterization of the sterically demanding ditopic lithium bis(pyrazol‐1‐yl)borates Li2[p‐C6H4(B(Ph)pzR2)2] is reported (pzR = 3‐phenylpyrazol‐1‐yl ( 3 Ph), 3‐t‐butylpyrazol‐1‐yl ( 3 tBu)). Compound 3 Ph crystallizes from THF as THF‐adduct 3 Ph(THF)4 which features a straight conformation with a long Li···Li distance of 12.68(1) Å. Compound 3 tBu was found to function as efficient and selective scavenger of chloride ions. In the presence of LiCl it forms anionic complexes [ 3 tBuCl]− with a central Li‐Cl‐Li core (Li···Li = 3.75(1) Å). 相似文献
7.
The mononuclear amidinate complexes [(η6‐cymene)‐RuCl( 1a )] ( 2 ) and [(η6‐C6H6)RuCl( 1b )] ( 3 ), with the trimethylsilyl‐ethinylamidinate ligands [Me3SiC≡CC(N‐c‐C6H11)2]– ( 1a– ) and[Me3SiC≡CC(N‐i‐C3H7)2]– ( 1b– ) were synthesized in high yields by salt metathesis. In addition, the related phosphane complexes[(η5‐C5H5)Ru(PPh3)( 1b )] ( 4a ) [(η5‐C5Me5)Ru(PPh3)( 1b )] ( 4b ), and [(η6‐C6H6)Ru(PPh3)( 1b )](BF4) ( 5 ‐BF4) were prepared by ligand exchange reactions. Investigations on the removal of the trimethyl‐silyl group using [Bu4N]F resulted in the isolation of [(η6‐C6H6)Ru(PPh3){(N‐i‐C3H7)2CC≡CH}](BF4) ( 6 ‐BF4) bearing a terminal alkynyl hydrogen atom, while 2 and 3 revealed to yield intricate reaction mixtures. Compounds 1a / b to 6 ‐BF4 were characterized by multinuclear NMR (1H, 13C, 31P) and IR spectroscopy and elemental analyses, including X‐ray diffraction analysis of 1b , 2 , and 3 . 相似文献
8.
Reaction of divalent Sm(OAr)2(THF)3 (Ar = C6H2‐tert‐Bu3‐2,4,6; THF = tetrahydrofuran) with one equivalent of azobenzene in THF and crystallization of the product in diethyl ether afforded the title complex (ArO)2(THF)2Sm(η2‐N2Ph2)·Et2O in good yield. In the complex, the N? N bond length for the azobenzene species is lengthened. The two Sm? N bonds are equivalent, and their bond lengths are intermediate between the donor bond and the single bond. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
9.
Zhongbao Jian Prof. Dr. Dongmei Cui Prof. Dr. Zhaomin Hou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(9):2674-2684
A series of rare‐earth‐metal–hydrocarbyl complexes bearing N‐type functionalized cyclopentadienyl (Cp) and fluorenyl (Flu) ligands were facilely synthesized. Treatment of [Y(CH2SiMe3)3(thf)2] with equimolar amount of the electron‐donating aminophenyl‐Cp ligand C5Me4H‐C6H4‐o‐NMe2 afforded the corresponding binuclear monoalkyl complex [({C5Me4‐C6H4‐o‐NMe(μ‐CH2)}Y{CH2SiMe3})2] ( 1 a ) via alkyl abstraction and C? H activation of the NMe2 group. The lutetium bis(allyl) complex [(C5Me4‐C6H4‐o‐NMe2)Lu(η3‐C3H5)2] ( 2 b ), which contained an electron‐donating aminophenyl‐Cp ligand, was isolated from the sequential metathesis reactions of LuCl3 with (C5Me4‐C6H4‐o‐NMe2)Li (1 equiv) and C3H5MgCl (2 equiv). Following a similar procedure, the yttrium‐ and scandium–bis(allyl) complexes, [(C5Me4‐C5H4N)Ln(η3‐C3H5)2] (Ln=Y ( 3 a ), Sc ( 3 b )), which also contained electron‐withdrawing pyridyl‐Cp ligands, were also obtained selectively. Deprotonation of the bulky pyridyl‐Flu ligand (C13H9‐C5H4N) by [Ln(CH2SiMe3)3(thf)2] generated the rare‐earth‐metal–dialkyl complexes, [(η3‐C13H8‐C5H4N)Ln(CH2SiMe3)2(thf)] (Ln=Y ( 4 a ), Sc ( 4 b ), Lu ( 4 c )), in which an unusual asymmetric η3‐allyl bonding mode of Flu moiety was observed. Switching to the bidentate yttrium–trisalkyl complex [Y(CH2C6H4‐o‐NMe2)3], the same reaction conditions afforded the corresponding yttrium bis(aminobenzyl) complex [(η3‐C13H8‐C5H4N)Y(CH2C6H4‐o‐NMe2)2] ( 5 ). Complexes 1 – 5 were fully characterized by 1H and 13C NMR and X‐ray spectroscopy, and by elemental analysis. In the presence of both [Ph3C][B(C6F5)4] and AliBu3, the electron‐donating aminophenyl‐Cp‐based complexes 1 and 2 did not show any activity towards styrene polymerization. In striking contrast, upon activation with [Ph3C][B(C6F5)4] only, the electron‐withdrawing pyridyl‐Cp‐based complexes 3 , in particular scandium complex 3 b , exhibited outstanding activitiy to give perfectly syndiotactic (rrrr >99 %) polystyrene, whereas their bulky pyridyl‐Flu analogues ( 4 and 5 ) in combination with [Ph3C][B(C6F5)4] and AliBu3 displayed much‐lower activity to afford syndiotactic‐enriched polystyrene. 相似文献
10.
Benjamin E. Kucera Robert E. Jilek William W. Brennessel John E. Ellis 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(8):749-753
Reduction of VCl3(THF)3 (THF is tetrahydrofuran) and NbCl4(THF)2 by alkali metal pyrene radical anion salts in THF affords the paramagnetic sandwich complexes bis[(1,2,3,3a,10a,10b‐η)‐pyrene]vanadium(0), [V(C16H10)2], and bis[(1,2,3,3a,10a,10b‐η)‐pyrene]niobium(0), [Nb(C16H10)2]. Treatment of tris(naphthalene)titanate(2−) with pyrene provides the isoelectronic titanium species, isolated as an (18‐crown‐6)potassium salt, namely catena‐poly[[(18‐crown‐6)potassium]‐μ‐[(1,2‐η:1,2,3,3a,10a,10b‐η)‐pyrene]‐titanate(−I)‐μ‐[(1,2,3,3a,10a,10b‐η:6,7‐η)‐pyrene]], {[K(C12H24O6)][Ti(C16H10)2]}n. The first two compounds have very similar packing, with neighboring molecules arranged orthogonally to one another, such that aromatic donor–acceptor interactions are likely responsible for the specific arrangement. The asymmetric unit contains a half‐occupancy metal center η6‐coordinated to one pyrene ligand, with the full M(pyrene)2 molecule generated by a crystallographic inversion center. In the titanium compound, the cations and anions are in alternating contact throughout the crystal structure, in one‐dimensional chains along the [101] direction. As in the other two compounds, the asymmetric unit contains a half‐occupancy Ti atom η6‐coordinated to one pyrene ligand. Additionally, the asymmetric unit contains one half of an (18‐crown‐6)potassium cation, located on a crystallographic inversion center coincident with the K atom. The full formula units are generated by those inversion centers. In all three structures, the pyrene ligands are eclipsed and sandwich the metals in one of two inversion‐related sites. These species are of interest as the first isolable homoleptic pyrene transition metal complexes to be described in the scientific literature. 相似文献
11.
Herbert Schumann Esther C. E. Rosenthal Jrg Demtschuk Stefan Mühle 《无机化学与普通化学杂志》2000,626(10):2161-2166
Organometallic Compounds of the Lanthanides. 139 Mixed Sandwich Complexes of the 4 f Elements: Enantiomerically Pure Cyclooctatetraenyl Cyclopentadienyl Complexes of Samarium and Lutetium with Donor‐Functionalized Cyclopentadienyl Ligands The reactions of [K{(S)‐C5H4CH2CH(Me)OMe}], [K{(S)‐C5H4CH2CH(Me)NMe2}] and [K{(S)‐C5H4CH(Ph)CH2NMe2}] with the cyclooctatetraenyl lanthanide chlorides [(η8‐C8H8)Ln(μ‐Cl)(THF)]2 (Ln = Sm, Lu) yield the mixed cyclooctatetraenyl cyclopentadienyl lanthanide complexes [(η8‐C8H8)Sm{(S)‐η5 : η1‐C5H4CH2CH(Me)OMe}] ( 1 a ), [(η8‐C8H8)Ln{(S)‐η5 : η1‐C5H4CH2CH(Me)NMe2}] (Ln = Sm ( 2 a ), Lu ( 2 b )) and [(η8‐C8H8)Ln{(S)‐η5 : η1‐C5H4CH(Ph)CH2NMe2}] (Ln = Sm ( 3 a ), Lu ( 3 b )). For comparison, the achiral compounds [(η8‐C8H8)Ln{η5 : η1‐C5H4CH2CH2NMe2}] (Ln = Sm ( 4 a ), Lu ( 4 b )) are synthesized in an analogous manner. 1H‐, 13C‐NMR‐, and mass spectra of all new compounds as well as the X‐ray crystal structures of 3 b and 4 b are discussed. 相似文献
12.
Rico Packheiser Tobias Rüffer Petra Ecorchard Prof. Dr. Heinrich Lang 《无机化学与普通化学杂志》2010,636(15):2607-2616
The synthesis of a unique series of heteromultinuclear transition metal compounds is reported. Complexes 1‐I‐3‐Br‐5‐(FcC≡C)‐C6H3 ( 4 ), 1‐Br‐3‐(bpy‐C≡C)‐5‐(FcC≡C)‐C6H3 ( 6 ), 1,3‐(bpy‐C≡C)2‐5‐(FcC≡C)‐C6H3 ( 7 ), 1‐(XC≡C)‐3‐(bpy‐C≡C)‐5‐(FcC≡C)‐C6H3 ( 8 , X = SiMe3; 9 , X = H), 1‐(HC≡C)‐3‐[(CO)3ClRe(bpy‐C≡C)]‐5‐(FcC≡C)‐C6H3 ( 11 ), 1‐[(Ph3P)AuC≡C]‐3‐[(CO)3ClRe(bpy‐C≡C)]‐5‐(FcC≡C)‐C6H3 ( 13 ), 1‐[(Ph3P)AuC≡C]‐3‐(bpy‐C≡C)‐5‐(FcC≡C)‐C6H3 ( 14 ), [1‐[(Ph3PAuC≡C]‐3‐[{[Ti](C≡CSiMe3)2}Cu(bpy‐C≡C)]‐5‐(FcC≡C)‐C6H3]PF6 ( 16 ), and [1,3‐[(tBu2bpy)2Ru(bpy‐C≡C)]2‐5‐(FcC≡C)‐C6H3](PF6)4 ( 18 ) (Fc = (η5‐C5H4)(η5‐C5H5)Fe, bpy = 2,2′‐bipyridiyl‐5‐yl, [Ti] = (η5‐C5H4SiMe3)2Ti) were prepared by using consecutive synthesis methodologies including metathesis, desilylation, dehydrohalogenation, and carbon–carbon cross‐coupling reactions. In these complexes the corresponding metal atoms are connected by carbon‐rich bridging units comprising 1,3‐diethynyl‐, 1,3,5‐triethynylbenzene and bipyridyl units. They were characterized by elemental analysis, IR and NMR spectroscopy, and partly by ESI‐TOF mass spectrometry., The structures of 4 and 11 in the solid state are reported. Both molecules are characterized by the central benzene core bridging the individual transition metal complex fragments. The corresponding acetylide entities are, as typical, found in a linear arrangement with representative M–C, C–CC≡C and C≡C bond lengths. 相似文献
13.
Univalent Gallium Complexes of Simple and ansa‐Arene Ligands: Effects on the Polymerization of Isobutylene
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Martin R. Lichtenthaler Steffen Maurer Robert J. Mangan Florian Stahl Florian Mönkemeyer Julian Hamann Prof. Dr. Ingo Krossing 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):157-165
Using [Ga(C6H5F)2]+[Al(ORF)4]?( 1 ) (RF=C(CF3)3) as starting material, we isolated bis‐ and tris‐η6‐coordinated gallium(I) arene complex salts of p‐xylene (1,4‐Me2C6H4), hexamethylbenzene (C6Me6), diphenylethane (PhC2H4Ph), and m‐terphenyl (1,3‐Ph2C6H4): [Ga(1,4‐Me2C6H4)2.5]+ ( 2+ ), [Ga(C6Me6)2]+ ( 3+ ), [Ga(PhC2H4Ph)]+ ( 4+ ) and [(C6H5F)Ga(μ‐1,3‐Ph2C6H4)2Ga(C6H5F)]2+ ( 52+ ). 4+ is the first structurally characterized ansa‐like bent sandwich chelate of univalent gallium and 52+ the first binuclear gallium(I) complex without a Ga?Ga bond. Beyond confirming the structural findings by multinuclear NMR spectroscopic investigations and density functional calculations (RI‐BP86/SV(P) level), [Ga(PhC2H4Ph)]+[Al(ORF)4]?( 4 ) and [(C6H5F)Ga(μ‐1,3‐Ph2C6H4)2Ga(C6H5F)]2+{[Al(ORF)4] ?}2 ( 5 ), featuring ansa‐arene ligands, were tested as catalysts for the synthesis of highly reactive polyisobutylene (HR‐PIB). In comparison to the recently published 1 and the [Ga(1,3,5‐Me3C6H3)2]+[Al(ORF)4]? salt ( 6 ) (1,3,5‐Me3C6H3=mesitylene), 4 and 5 gave slightly reduced reactivities. This allowed for favorably increased polymerization temperatures of up to +15 °C, while yielding HR‐PIB with high contents of terminal olefinic double bonds (α‐contents=84–93 %), low molecular weights (Mn=1000–3000 g mol?1) and good monomer conversions (up to 83 % in two hours). While the chelate complexes delivered more favorable results than 1 and 6 , the reaction kinetics resembled and thus concurred with the recently proposed coordinative polymerization mechanism. 相似文献
14.
The o‐substituted hybrid phenylphosphines, PPh2(o‐C6H4NH2) and PPh2(o‐C6H4OH), could be deprotonated with LDA or n‐BuLi to yield PPh2(o‐C6H4NHLi) and PPh2(o‐C6H4OLi), respectively. When added to a solution of (η5‐C5H5)Fe(CO)2I at room temperature, these two lithiated reagents produce a chelated neutral complex 1 (η5‐C5H5)Fe(CO)[C(O)NH(o‐C6H4)PPh2‐C,P‐η2] for the former and mainly a zwitterionic complex 2 , (η5‐C5H5)Fe+(CO)2[PPh2(o‐C6H4O?)] for the latter. Complex 1 could easily be protonated and then decarbonylated to give 4 [(η5‐C5H5)Fe(CO){NH2(o‐C6H4)PPh2‐N,P‐η2}+]. Complexes 1 and 4‐I have been crystallographically characterized with X‐ray diffraction. 相似文献
15.
The ability of transition metal catalysts to add or remove hydrogen from organic substrates by transfer hydrogenation is a valuable synthetic tool. Towards a series of novel metal complexes with a P―NH ligand, [Ph2PNHCH2―C4H3O] derived from furfurylamine were synthesized. Reaction of [Ph2PNHCH2―C4H3O] 1 with [Ru(η6‐p‐cymene)(μ‐Cl)Cl]2, [Ru(η6‐benzene)(μ‐Cl)Cl]2, [Rh(μ‐Cl)(cod)]2 and [Ir(η5‐C5Me5)(μ‐Cl)Cl]2 gave a range of new monodentate complexes [Ru(Ph2PNHCH2―C4H3O)(η6‐p‐cymene)Cl2] 2 , [Ru(Ph2PNHCH2―C4H3O)(η6‐benzene)Cl2] 3 , [Rh(Ph2PNHCH2‐C4H3O)(cod)Cl] 4 , and [Ir(Ph2PNHCH2‐C4H30)(η5‐C5Me5)Cl2] 5 , respectively. All new complexes were fully characterized by analytical and spectroscopic methods. 31P‐{1H} NMR, distortionless enhancement by polarization transfer (DEPT) or 1H‐13C heteronuclear correlation (HETCOR) experiments were used to confirm the spectral assignments. Following activation by KOH, compounds 1 , 2 , 3 , 4 catalyzed the transfer hydrogenation of acetophenone derivatives to 1‐phenylethanol derivatives in the presence of iso‐PrOH as the hydrogen source. Notably [Ru(Ph2PNHCH2‐C4H3O)(η6‐benzene)Cl2] 3 acts as an excellent catalyst, giving the corresponding alcohols in 98–99% yield in 20 min at 82°C (time of flight ≤ 297 h?1) for the transfer hydrogenation reaction in comparison to analogous rhodium or iridium complexes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
16.
Prof. Dr. Holger Braunschweig Marco Fuß Dr. Swagat K. Mohapatra Katharina Kraft Dr. Thomas Kupfer Melanie Lang Dr. Krzysztof Radacki Dr. Constantin G. Daniliuc Prof. Dr. Peter G. Jones Prof. Dr. Matthias Tamm 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(38):11732-11743
A novel one‐pot method was developed for the preparation of [Ti(η5‐C5H5)(η7‐C7H7)] (troticene, 1 ) by reaction of sodium cyclopentadienide (NaCp) with [TiCl4(thf)2], followed by reduction of the intermediate [(η5‐C5H5)2TiCl2] with magnesium in the presence of cycloheptatriene (C7H8). The [n]troticenophanes 3 (n=1), 4 , 8 , 10 (n=2), and 11 (n=3) were synthesized by salt elimination reactions between dilithiated troticene, [Ti(η5‐C5H4Li)(η7‐C7H6Li)] ? pmdta ( 2 ) (pmdta=N,N′,N′,N′′,N′′‐pentamethyldiethylenetriamine), and the appropriate organoelement dichlorides Cl2Sn(Mes)2 (Mes=2,4,6‐trimethylphenyl), Cl2Sn2(tBu)4, Cl2B2(NMe2)2, Cl2Si2Me4, and (ClSiMe2)2CH2, respectively. Their structural characterization was carried out by single‐crystal X‐ray diffraction and multinuclear NMR spectroscopy. The stanna[1]‐ and stanna[2]troticenophanes 3 and 4 represent the first heteroleptic sandwich complexes bearing Sn atoms in the ansa bridge. The reaction of 3 with [Pt(PEt3)3] resulted in regioselective insertion of the [Pt(PEt3)2] fragment into the Sn? Cipso bond between the tin atom and the seven‐membered ring, which afforded the platinastanna[2]troticenophane 5 . Oxidative addition was also observed upon treatment of 4 with elemental sulfur or selenium, to produce the [3]troticenophanes [Ti(η5‐C5H4SntBu2)(η7‐C7H6SntBu2)E] ( 6 : E=S; 7 : E=Se). The B? B bond of the bora[2]troticenophane 8 was readily cleaved by reaction with [Pt(PEt3)3] to form the corresponding oxidative addition product [Ti(η5‐C5H4BNMe2)(η7‐C7H6BNMe2)Pt(PEt3)2] ( 9 ). The solid‐state structures of compounds 5 , 6 , and 9 were also determined by single‐crystal X‐ray diffraction. 相似文献
17.
The title coordination polymer, poly[[aqua(μ5‐1,1′‐biphenyl‐2,2′,5,5′‐tetracarboxylato)bis[μ2‐1,4‐bis(1H‐imidazol‐1‐yl)benzene]dicadmium(II)] dihydrate], {[Cd2(C16H6O8)(C12H10N4)2(H2O)]·2H2O}n, was crystallized from a mixture of 1,1′‐biphenyl‐2,2′,5,5′‐tetracarboxylic acid (H4bpta), 1,4‐bis(1H‐imidazol‐1‐yl)benzene (1,4‐bib) and cadmium nitrate in water–dimethylformamide. The crystal structure consists of two crystallographically independent CdII cations, with one of the CdII cations possessing a slightly distorted pentagonal bipyramidal geometry. The second CdII centre is coordinated by carboxylate O atoms and imidazole N atoms from two separate 1,4‐bib ligands, displaying a distorted octahedral CdN2O4 geometry. The completely deprotonated bpta4− ligand, exhibiting a new coordination mode, bridges five CdII cations to form one‐dimensional chains viaμ3‐η1:η2:η1:η2 and μ2‐η1:η1:η0:η0 modes, and these are further linked by 1,4‐bib ligands to form a three‐dimensional framework with a (42.64)(4.62)(43.65.72) topology. The structure of the coordination polymer is reinforced by intermolecular hydrogen bonding between carboxylate O atoms, aqua ligands and crystallization water molecules. The solid‐state photoluminescence properties were investigated and the complex might be a candidate for a thermally stable and solvent‐resistant blue fluorescent material. 相似文献
18.
Synthesis, Structure, and Reactivity of η1‐ and η3‐Allyl Rhenium Carbonyls In (η3‐C3H5)Re(CO)4 one CO ligand can be substituted by PPh3, pyridine, isocyanide and benzonitrile. With 1,2‐bis(diphenylphosphino)ethylene, 1,1′‐bis(diphenylphosphino)ferrocene and 1,2‐bis(4‐pyridyl)ethane dinuclear ligand bridged complexes are obtained. The η3‐η1 conversion of the allyl ligand occurs on reaction of (η3‐C3H5)Re(CO)4 with the bidendate ligands 1,2‐bis(diphenylphosphino)ethane and 1,3‐bis(diphenylphosphino)propane and with 2,2′‐bipyridine (L–L) which gives the complexes (η1‐C3H5)Re(CO)3(L–L). By reaction of (η3‐C3H5)Re(CO)4 with bis(diphenylphosphino)methane the allyl group is protonated and under elemination of propene the complex (OC)3Re(Ph2PCHPPh2)(η1‐Ph2PCH2PPh2) ( 19 ) with a diphosphinomethanide ligand is formed. On heating solutions of (η3‐C3H5)Re(CO)4 and (η3‐C3H5)Re(CO)3(CN‐2,5‐Me2C6H3) ( 5 ) in methanol the methoxy bridged compounds Re4(CO)12(OH)(OMe)3 and Re2(CO)4(CN‐2,5‐Me2C6H3)4(μ‐OMe)2 ( 20 ) were isolated. The crystal structures of (η3‐C3H5)Re(CO)3(CNCH2SiMe3) ( 4 ), [(η3‐C3H5)(OC)3Re]2‐ (μ‐bis‐(diphenylphosphino)ferrocene) ( 8 ), (η1‐C3H5)Re(CO)3‐ (bpy) ( 14 ), of 19 , 20 and of (OC)3Re‐[Ph2P(CH2)3PPh2]Cl ( 16 ) were determined by X‐ray diffraction. 相似文献
19.
Julia Hitzbleck 《Journal of organometallic chemistry》2007,692(21):4702-4707
Half-sandwich dibenzyl complexes of scandium have been prepared by stepwise treatment of scandium trichloride with lithium derivatives of silyl-functionalized tetramethylcyclopentadienes (C5Me4H)SiMe2R (R = Me, Ph) and benzyl magnesium chloride. The resulting complexes [Sc(η5-C5Me4SiMe3)(CH2Ph)2(THF)] and [Sc(η5-C5Me4SiMe2Ph)(CH2Ph)2(1,4-dioxane)] show structure related to that of the corresponding bis(trimethylsilylmethyl) compounds [Sc(η5-C5Me4SiMe2R)(CH2SiMe3)2(THF)]. The four-coordinate complexes display η1-coordinated benzyl ligands without significant interaction of the ipso-carbon of the phenyl moiety. Conversion of [Sc(η5-C5Me4SiMe3)(CH2Ph)2(THF)] into the cationic species by treatment with triphenylborane in THF led to the formation of a stable charge separated complex [Sc(η5-C5Me4SiMe3)(CH2Ph)(THF)x][BPh3(CH2Ph)]. Benzyl cation formed using [Ph3C][B(C6F5)4] in toluene resulted in a moderately active syndiospecific styrene polymerization catalyst. 相似文献
20.
Dominique Robert Dr. Elise Abinet Dipl.‐Chem. Thomas P. Spaniol Dr. Jun Okuda Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(44):11937-11947
Monocationic bis‐allyl complexes [Ln(η3‐C3H5)2(thf)3]+[B(C6X5)4]? (Ln=Y, La, Nd; X=H, F) and dicationic mono‐allyl complexes of yttrium and the early lanthanides [Ln(η3‐C3H5)(thf)6]2+[BPh4]2? (Ln=La, Nd) were prepared by protonolysis of the tris‐allyl complexes [Ln(η3‐C3H5)3(diox)] (Ln=Y, La, Ce, Pr, Nd, Sm; diox=1,4‐dioxane) isolated as a 1,4‐dioxane‐bridged dimer (Ln=Ce) or THF adducts [Ln(η3‐C3H5)3(thf)2] (Ln=Ce, Pr). Allyl abstraction from the neutral tris‐allyl complex by a Lewis acid, ER3 (Al(CH2SiMe3)3, BPh3) gave the ion pair [Ln(η3‐C3H5)2(thf)3]+[ER3(η1‐CH2CH?CH2)]? (Ln=Y, La; ER3=Al(CH2SiMe3)3, BPh3). Benzophenone inserts into the La? Callyl bond of [La(η3‐C3H5)2(thf)3]+[BPh4]? to form the alkoxy complex [La{OCPh2(CH2CH?CH2)}2(thf)3]+[BPh4]?. The monocationic half‐sandwich complexes [Ln(η5‐C5Me4SiMe3)(η3‐C3H5)(thf)2]+[B(C6X5)4]? (Ln=Y, La; X=H, F) were synthesized from the neutral precursors [Ln(η5‐C5Me4SiMe3)(η3‐C3H5)2(thf)] by protonolysis. For 1,3‐butadiene polymerization catalysis, the yttrium‐based systems were more active than the corresponding lanthanum or neodymium homologues, giving polybutadiene with approximately 90 % 1,4‐cis stereoselectivity. 相似文献