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1.
Under suitable reactant ratios without sublimation or reerystallization, single crystals of(η~5-C_5,H_5)_3 Ln-OC_4H_8(In = La, Pr, Nd) could be prepared by the reaction of cyclopentadienylsodium with respective lanthanide trichlorides in THF. Using low temperature technique wehave collected the X-ray data of single crystals of the title compounds at -60℃ under N_2and determined crystal structures. (η~5-C_5H_5)_3 Pr·OC_4H_8, [(η_5-C_5H_5)_3 Nd·OC_4H_8] recrystallizesin the monoclinic space group P2_1/n[P2_1/n] with unit cell parameters a = 8.406(3) [8.364(3)],b = 24. 510(9) [24.467(9)], c = 8. 284(3) [8.254(3)] A, β= 101.60(3) [101.42 (3)], D_c = 1. 62 [1.65]gem~(-3) for z = 4 [4]. Least-square refinement has led to a final R value of 0.056 [0.063],R_W = 0.049 [0.062]. The THF molecule is coordinated to the Pr [Nd] atom at a Pr-O [Nd-O]bond length of 2.16(1) [2.54(1)], A. The Pr-C (Cp) [Nd-C(Cp)] bond distances average 2.80(2) [2.78(2)] A. The title compounds are isostructaral with (η~5-C_5H_5)_3 相似文献
2.
1 INTRODUCTION The chemistry of transition metal cluster has enjoyed an exceptional growth since the mid 1970s[1, 2], especially in recent years the structural and bonding aspects of mixed-metal tetrahedral skeleton clusters have been extensively studied[3]. One important reason is that such chiral cluster can induce an asymmetric catalysis potentially. In our research group, considerable efforts have been directed to the synthesis of chiral tetrahedral clusters containing four different… 相似文献
3.
4.
合成了(η~5-C_5H_5)_2Nb[CH_2Si(CH_3)_3]_2化合物,并测定了它的晶体结构及溶液和玻璃态固体的EPR;通过计算机模拟玻璃态固体EPR得到了g和T的分量;测得最高占据分子轨道的a~2/b~2=10.3。 相似文献
5.
1 INTRODUCTION Manganese has been implicated as an essential part of the active center in various manganese enzymes. Various nuclearities have been observed from mononuclear atom in superoxide dismutase [1] to the tetranuclear atom of oxygen evolution in photosystem II[2]. The manganese active centers in biological systems are surrounded by O and N coordination sphere[3, 4]. Synthetic efforts have produced a great variety of Mn clusters with varying nuclearity and oxidation states. Si… 相似文献
6.
1 INTRODUCTION The complexes of syn- or anti-[(5-C5Me5)2- W2(S)2(-S)2] could be prepared in several ways[1~5]. For example, a mixture consisting of [Et3NH][(5-C5Me5)WS3] and anti-[(5-C5Me5)2- W2(S)2(-S)2] was generated from the reactions of [(5-C5Me5)WCl4] with H2S in the presence of NEt3[2]. The reactions of [(5-C5Me5)W(NO)I2] with H2S led a mixture of [(5-C5Me5)W(S)(S2)I] and anti-[(5-C5Me5)2W2(S)2(-S)2][3]. [(5-C5Me5)W- (StBu)3] was degraded in THF at room temperat… 相似文献
7.
The reaction of LnCl_3 with K _9H_7(C_9H_7=indenyl)andK_2C_8H_8(C_8H_8=cyclooctatetraene)in tetrahydrofuran(THF)give thecorresponding complexes(η~5-C_9H_7)Ln(η~8-C_8H_8)·2THF.The synthesis of(η~5-C_9H_7)Ln(η~8-C_8H_8)·2THF(Ln=Pr,Nd)and crystal structure of(η~5-C_9H_7)Pr(η~8-C_8H_8)·2THF are described. 相似文献
8.
本文用LnCl_3(Ln=La,Pr,Nd)同环戊二烯钠在THF溶液中反应,制备出(η~5-C_5H_5)_3Ln·OC_4H_8化合物单晶.采用低温技术,在—60℃的干燥氮气保护下,收集(η~5-C_5H_5)_3HPr·OC_4H_8[(η~5-C_5H_5)Nd·OC_4H_8]的单晶X射线衍射数据,解出了晶体结构.它们同属单斜晶系,P2_1/n 空间群.结构表明,THF分子中的氧原子与金属离子键合,Pr—O键长为2.56(1)A,Nd—O键长为2.54(1)A.三个环戊二烯分子中的所有碳原子与金属离子的间距,均在成键范围,其平均键距Pr—C为2.80(2)A,Nd—C为2.78(2)A.它们同已报道的(η~5-C_5H_5Ln·OC_4H_8(Ln=Y,La,Gd)结构一起,可很好地解释镧系收缩理论,同时为研究稀土元素的价态和键,提供了有用的结构信息。 相似文献
9.
《结构化学》1991,(3)
<正> C35.5H31FePdCl2O0.5P2 ({dichloro-[1,1' -bis (diphenyl) phosphino]-fer-rocene}palladium (Ⅱ) hemi acetone solvate) ,Mr = 760. 74,monoclinic,space group C2/ c,a=33. 993(4),b=10. 424(3),c=18. 364(4) A ,β=104. 52(1)°,V = 6299A3,Z= 8,DC=1.67 g/cm3,μ= 13. 3cm-1,F(000) = 3200,final R= 0.075 for 2058 observed reflections. The environment of the Pd atom is described as a square plane with two cis-chlorine atoms and two phosphorus atoms. The [1, 1'-bisdiphenylphospino] ferrocene (dppf) group is connected to the Pd atom as a bidentate ligand. The Pd-P distances are 2. 278(5) and 2. 278(6) A ;the Pd-Cl distances 2. 323(6) and 2. 345(6) A. 相似文献
10.
标题配合物是以THF作溶剂,通过(C_5H_5)_2NdCl·ZLiCl和甲基萘钠的还原反应合成的。其晶体属单斜晶系,P 2/c空间群,晶胞参数α=9.235(2)A,b=11.695(2)A,c=20.810(3)A,β=92.88(1)°,Z=2。研究结果表明,标题配合物由相互不相联的〔Li3DME〕~ 和〔(η~5-C_5H_5)_3Nd(μ-H)Nd(η~5-C_5H_5)_3〕~-离子对组成。阳离子中,Li原子与由3个DME提供的6个O原子配位,形成八面体构型,Li—O平均键长为2.116A;阴离子中,2个Nd原子不直接键合,系通过桥H联接,Nd—H=2.19A。此外,每个Nd原子各有3个C_5H_5~-与之配位,Nd—C平均键长为2.812A。 相似文献
11.
1 INTRODUCTION We once reported a CS bond cleavage reaction of (h5-C5Me5)Mo(StBu)3, which led to a Mo(IV) thio/thiolate complex (h5-C5Me5)MoS2(StBu)[1]. This reaction was facilitated by oxidants such as S8, gray selenium, and FeCl3[2]. The reaction with FeCl3 gave rise to a cubane cluster [(h5-C5Me5)2Mo2Fe2S4Cl2], which served as an excellent building block to construct various Mo/Fe/S clusters[2]. In this paper, we report the crystal structure of [(h5-C5Me5)2Mo2Fe… 相似文献
12.
1 INTRODUCTION It is well known that lanthanide metals are quite oxophilic and the oxygen-stabilized organolanthanide complexes are tractable for exploring their physical and chemical properties. Organolanthanide complexes involving -diketonato chelate ligands have been largely prepared and characterized[1~5]. The Schiff base complexes are some of the most important stereochemical models in transition metal coordination chemistry; however, the organolanthanide Schiff base complexes are … 相似文献
13.
Thereactionsof6,6-dialkylfulveneswithactiveorganometal(Li,Na,Mg)reagentshavebeensystematicallystudiedin0urlab0ratory.Thesereactionsprovideapracticalpathwayforthepreparationofcyclopentadienylanions,inparticularthosewithbulkysubstituents,whichcanbereadilycoordinatedwithtransitionmetalhalidestopr0ducesubstitutedmetall0cenes(Ti,Zr,Fe)1.6,6-Dimethylfulvene0r6,6-pentamethylenefulvenecaneasilyundergoexocyclicdoublebondadditionreactionsbythetreatmentof(substituted)phenyllithiumt0givearylsubstitutedc… 相似文献
14.
铁羰基化合物的研究(η~5-C_5H_5)Fe(CO)_2CH_2COOR的合成 总被引:1,自引:0,他引:1
在我们实验室里采用环戊二烯基羰基铁的钠盐[(η~5-C_5H_5)Fe(CO)_2]Na和氯代乙酸酯ClCH_2COOR(R=C_2H_5,C_3H_7,C_4H_9,C_5H_(11))直接反应合成了铁羰基化合物(η~5-C_5H_5)Fe(CO)_2CH_2COOR(Ⅰ).并通过IR、~1H NMR、~(13)C NMR以及MS的分析,确定了(Ⅰ)的结构.η~5-环戊二烯基(2-烷氧基-2-氧代乙基)二羰基合铁(Ⅰ)的合成路线如下: 相似文献
15.
1INtrODUCTIONThethiophilicpropertyoftransitionmetalshasbeensuccessfullyusedforthesynthesisofsulfidocluster[li.ComPOundscontainingsulfidoligandsareimportantinvariousareasofmodernchemistry"--".WehaverePOrtedthesynthesesandstructuresofaserialmixedsulfidoclustersts'6i.Theelectrophilic--additionsubstituenteliminationreactionmechanismwasalsoproPOsed.Asapartofcontinuouswork,herewereportthesynthesisandcharacterizationofthetitlecluster.2EXPERIMENTALAlloperationswerecarriedoutunderhighlypure… 相似文献
16.
《中国化学快报》1993,(2)
The dynamic ~1H and ~(13)C-NMR studies on [Li(2D)][Nd(η~8-C_3H_5)_4](D=dioxane)were reported The four allyls coordinated to Hd~(8+) ion areequivalent and hydrogens appear as three groups in ~1H-NMR spectra with theirchemical shifts changing with temperature.C_1 and Ca are equivalent showing thecharacteristic of η~2=-allyl.The paramagnetic shifts of carbons in allylsinduced by Nd~(2+) ere separated sucessfully.C_1 and C_3 located on thezero-dipolar cone.The content of contact shift is greater than that of dipolarslift to Co. 相似文献
17.
双(茚基)镱(Ⅱ)四氢呋喃配合物(η~5-C_9H_7)_2Yb(THF)_2的晶体属单斜晶系,C_c空间群,晶体学参数a=13.506(4),b=11.081(2),c=15.577(5),β=92.68(3)°,V=2329(1),D_c=1.56g/cm~3,Z=4,μ=42.4cm~(-1),F(000)=1088,最终编离因子R=0.029,R_w=0.031。中心离子Yb~(2+)与两个茚基以η~5形式成键且与两个四氢呋喃中的氧成键,茚基的两个质心和四氢呋喃中的两个氧形成扭曲的四面体,Yb~(2+)在四面体的中心。Yb~(2+)的配位数为8。Yb~(2+)到质心In1的距离为2.52,到质心In2的距离为2.40。Yb~(2+)到O(1)的键长为2.356(7),到O(2)的键长为2.417(5)。 相似文献
18.
The title complex [Fc(OCH3)PS2Ir(cod)] (1, Fc = Fe(η5-C5H4)(η5-C5H5), cod = 1,5-cyclooctadiene) has been prepared and characterized by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/n with a = 12.5567(5), b = 13.5197(5), c = 11.7833(4) , β = 99.651(2)°, V = 1972.06(13) 3, Z = 4, Mr = 611.52, Dc = 2.06 g/cm3, μ(MoKα) = 7.775 mm·1, F(000) = 1184, S = 1.063, the final R = 0.0199 and wR = 0.0468 for 4063 observed reflections with I > 2σ(I) and 227 variables. The molecular structure of 1 shows that the central iridium atom is chelated by the [Fc(OCH3)PS2]-ligand via two sulfur atoms and coordinated by one η4-cod molecule via four carbon atoms in a distorted octahedral coordination geometry. The average Ir-S and Ir-C bond lengths are 2.3712(8) and 2.122(3) , respectively. 相似文献
19.
Hydrothermal Synthesis and Structure of a New Molybdenum Phosphate: (NH_3CH_2CH_2NH_3)_(2.5)[Mo_5O_(15)(PO_4) (HPO_4)]·7.5H_2O 总被引:2,自引:0,他引:2
1 INTRODUCTION A new class of materials of metal oxide clusters based on anionic molybdenum phosphate frameworks has received much attention as a consequence of their potential applications in catalysis and materials science [1]. As a result, some molybdenum phosphates have been studied [2,3]. Recently we have studied the structure of NaPMO material[4] and the spectrum of multicomponent compound with Keggin struc- ture [5]. Here we report the synthesis and crystal structure of a new… 相似文献
20.
《高等学校化学研究》1985,(1)
(η5-C6H5)2 NbcCH2Si(CH3)3]2 has been prepared and characterized by X-ray diffraction method and solution and frozen-glass EPR.The compound crystallizes in a monoclinic space group P21/O with lattice parameters a=13.291(A),b=12.406(A),σ=13.901A,β=115.40,V=2070A and Z=4 Full-matrix least-squares refinement of the diffractometry data led to final discrepancy indices of K(F0)=0.043,R(F02)=0.057,Rw(F02)=0.071.From computer simulation of the frozen-glass spec trum of the compound,the principal components of the g and T tensors are gx=1.9840.gy=2.0075,gz=2.0020,Tx=-89.2G,Ty=-136.9G,Tz=-50.0G.The observed anisotropy for the hyperfine interaction arises from the admixture of 4dz2 and 4dx2-y2 character in the HOMO.The ratio of mixing coefficients a2/b2=10.3. 相似文献