四羰基双[2,5-二(三甲硅基)-1-甲基环戊二烯基]

由甲基环戊二烯经两步类似反应向其环上引入两个Me3Si取代基, 生成(Me3Si)2-MeC5H3, 后者与Fe(CO)5反应除生成预期的双核Fe-Fe键产物[η^5-{Me3Si)2MeC5H2}Fe(CO)]2-(μ-CO)2(2)外, 还分离到小量单核化合物η^5-[(Me2Si)2MeC5H2]Fe(CO)2Cl(3), 2与碘反应生成Fe-Fe键断裂的单核铁碘化物(4)。2经Na/Hg还原生成Fe-Fe键断裂的铁负离子, 后者随即分别与数种氯化物反应, 生成在铁原子上引入相应取代基的铁衍生物η^5-[(Me3Si)2MeC5H2]Fe(CO)2R(R=PhCH2, 5; CH2COOC2H5, 6; Ph3Sn, 7; Ph2SnCl, 8)。测定了4的晶体结构, 晶体属单斜晶系, P21/c空间群, 晶胞参数a=0.7333(1), b=2.0089(3),c=1.3323(4)nm; β=92.02(2)°, V=1.962(1)nm^3, Z=4。     

Novel metal-to-metal silyl-migration reactions in heterometallic complexes

An unprecedented, intramolecular metal-to-metal silyl ligand migration reaction has been discovered in a series of phosphido-bridged iron-platinum complexes and which may be triggered by an external nucleophile. Thus, reaction of solutions of [(OC)3-(R1/3Si)Fe(mu-PR2R3)Pt(1,5-COD) (1a R1 = OMe, R2 = 3 = Ph; 1b R1 = OMe, R2 = R3 = Cy; 1c R1 = Ph, R2 = R3 = Ph; 1d R1 = Ph, R2 = R3 = Cy; 1e R1 = Ph, R1 = H, R3 = Ph) in CH2Cl2 with CO rapidly afforded the corresponding complexes [(OC)4Fe(mu-PR2R3)Pt(SiR1/3)-(CO)] (2a-e) in which the silyl ligand has migrated from Fe to Pt, while two CO ligands have been ligated, one on each metal. When 1a or 1c was slowly treated with two equivalents of tBuNC at low temperature, quantitative displacement of the COD ligand was accompagnied by silyl migration from Fe to Pt and coordination of an isonitrile ligand to Fe and to Pt to give [(OC)3-(tBuNC)Fe(mu-PPh2)Pt[Si(OMe)3](CNtBu)] (3a) and [(OC)3(tBuNC)-Fe(mu-PPh2)Pt[SiPh3](CNtBu)] (3c). Reaction of 2a with one equivalent of tBuNC selectively led to substitution of the Pt-bound CO to give [(OC)4-Fe(mu-PCy2)Pt[Si(OMe)3](CNtBu)] (4b), which reacted with a second equivalent of tBuNC to give [(OC)4Fe(mu-PCy2)-Pt[Si(OMe)3](CNtBu)2] (5b) in which the metal-metal bond has been cleaved. Opening of the Fe-Pt bond was also observed upon reaction of 3a with tBuNC to give [(OC)3(tBuNC)-Fe(mu-PPh2)Pt[Si(OMe)3](CNtBu)2] (6). The silyl ligand migrates from Fe, in which it is trans to mu-PR2R3 in all the metal-metal-bonded complexes, to a position cis to the phosphido bridge on Pt. However, in 5a,b and 6 with no metal-metal bond, the Pt-bound silyl ligand is trans to the phosphido bridge. The intramolecular nature of the silyl migration, which may be formally viewed as a redox reaction, was established by a cross-over experiment consisting of the reaction of 1a and 1d with CO; this yielded exclusively 2a and 2d. The course of the silyl-migration reaction was found to depend a) on the steric properties of the -SiR1/3 ligand, and for a given mu-PR2R3 bridge (R2 = R3 = Ph), the migration rate decreases in the sequence Si(OMe)3> SiMe2Ph> SiMePh2>SiPh3; b) on the phosphido bridge and for a given silyl ligand (R1 = OMe), the migration rate decreases in the order mu-PPh2 > mu-PHCy; c) on the external nucleophile since reaction of 1c with two equivalents of P(OMe)3, P(OPh)3 or Ph2PCH2C(O)Ph led solely to displacement of the COD ligand with formation of 11a-c, respectively, whereas reaction with two equivalents of tBuNC gave the product of silyl migration 3c. Reaction of [(OC)3-[(MeO)3Si]Fe(mu-PPh2)Pt(PPh3)2] (7a) with tBuNC (even in slight excess) occurred stereoselectively with replacement of the PPh3 ligand trans to mu-PPh2, whereas reaction with CO led first to [(OC)3((MeO)3Si)Fe(mu-PPh2)Pt(CO)-(PPh3)] (8a), which then isomerized to the migration product [(OC)4Fe(mu-PPh2)Pt[Si(OMe)3](PPh3)] (9a). Most complexes were characterized by elemental analysis, IR and 1H, 31P, 13C, and 29Si NMR spectroscopy, and in five cases by X-ray diffraction.     

Formation and chemical reactivities of a new type of double-butterfly [[Fe2(mu-CO)(CO)6]2(mu-SZS-mu)]2-: synthetic and structural studies on novel linear and macrocyclic butterfly Fe/E (E=S,Se) cluster complexes

A new type of double-butterfly [[Fe(2)(mu-CO)(CO)(6)](2)(mu-SZS-mu)](2-) (3), a dianion that has two mu-CO ligands, has been synthesized from dithiol HSZSH (Z=(CH(2))(4), CH(2)(CH(2)OCH(2))(1-3)CH(2)), [Fe(3)(CO)(12)], and Et(3)N in a molar ratio of 1:2:2 at room temperature. Interestingly, the in situ reactions of dianions 3 with various electrophiles affords a series of novel linear and macrocyclic butterfly Fe/E (E=S, Se) cluster complexes. For instance, while reactions of 3 with PhC(O)Cl and Ph(2)PCl give linear clusters [[Fe(2)(mu-PhCO)(CO)(6)](2)(mu-SZS-mu)] (4 a,b: Z=CH(2)(CH(2)OCH(2))(2,3)CH(2)) and [[Fe(2)(mu-Ph(2)P)(CO)(6)](2)(mu-SZS-mu)] (5 a,b: Z=CH(2)(CH(2)OCH(2))(2,3)CH(2)), reactions with CS(2) followed by treatment with monohalides RX or dihalides X-Y-X give both linear clusters [[Fe(2)(mu-RCS(2))(CO)(6)](2)(mu-SZS-mu)] (6 a-e: Z=CH(2)(CH(2)OCH(2))(1,2)CH(2); R=Me, PhCH(2), FeCp(CO)(2)) and macrocyclic clusters [[Fe(2)(CO)(6)](2)(mu-SZS-mu)(mu-CS(2)YCS(2)-mu)] (7 a-e: Z=(CH(2))(4), CH(2)(CH(2)OCH(2))(1-3)CH(2); Y=(CH(2))(2-4), 1,3,5-Me(CH(2))(2)C(6)H(3), 1,4-(CH(2))(2)C(6)H(4)). In addition, reactions of dianions 3 with [Fe(2)(mu-S(2))(CO)(6)] followed by treatment with RX or X-Y-X give linear clusters [[[Fe(2)(CO)(6)](2)(mu-RS)(mu(4)-S)](2)(mu-SZS-mu)] (8 a-c: Z=CH(2)(CH(2)OCH(2))(1,2)CH(2); R=Me, PhCH(2)) and macrocyclic clusters [[[Fe(2)(CO)(6)](2)(mu(4)-S)](2)(mu-SYS-mu)(mu-SZS-mu)] (9 a,b: Z=CH(2)(CH(2)OCH(2))(2,3)CH(2); Y=(CH(2))(4)), and reactions with SeCl(2) afford macrocycles [[Fe(2)(CO)(6)](2)(mu(4)-Se)(mu-SZS-mu)] (10 d: Z=CH(2)(CH(2)OCH(2))(3)CH(2)) and [[[Fe(2)(CO)(6)](2)(mu(4)-Se)](2)(mu-SZS-mu)(2)] (11 a-d: Z=(CH(2))(4), CH(2)(CH(2)OCH(2))(1-3)CH(2)). Production pathways have been suggested; these involve initial nucleophilic attacks by the Fe-centered dianions 3 at the corresponding electrophiles. All the products are new and have been characterized by combustion analysis and spectroscopy, and by X-ray diffraction techniques for 6 c, 7 d, 9 b, 10 d, and 11 c in particular. X-ray diffraction analyses revealed that the double-butterfly cluster core Fe(4)S(2)Se in 10 d is severely distorted in comparison to that in 11 c. In view of the Z chains in 10 a-c being shorter than the chain in 10 d, the double cluster core Fe(4)S(2)Se in 10 a-c would be expected to be even more severely distorted, a possible reason for why 10 a-c could not be formed.     

Synthesis and Crystal Structure of （SiCl3）2Fe（CO）4

The compound （SiCl3）2Fe（CO）4 was synthesized and structurally characterized by X-ray single-crystal diffraction. It crystallizes in monoclinic, space group P2 1/n with α = 8.287（2）, b = 9.829（2）, c = 9.042（2） A, β = 96.19（3）°, V= 732.2（3） A^3, C4Cl6FeO4Si2, Mr = 436.77, Z = 2, Dc = 1.981 g/cm^3, F（000） = 424, μ（MoKα） = 2.282 mm^-1, the final R = 0.048 and wR = 0.164 for 1109 observed reflections （I 〉 2σ（I））. The crystal structure of （SiCl3）2Fe（CO）4 reveals that the Si（l）- Fe-Si（l）^a sequence is linear and perpendicular to the Fe（CO）4 cross-shaped plane.     

Oxidative Addition vs. Ligand-Exchange: Fe(II)-Mixed-Phenylchalcogenolate Complexes fac-[PPN][Fe(CO)3(TePh)n(SePh)3-N] (n = 1, 2)

Diphenyldichalcogenides (PhE)₂ (E = Te, Se) react with Fe(0)-phenylchalcogenolate [PPN] [PhEFe(CO)₄] to yield the products of oxidative addition, Fe(II)-mixed-phenylchalcogenolate fac- [PPN][Fe(CO)₃(TePh)_n(ScPh)_3-n] (n = 1, 2). Reactions of [PPN][REFe(CO)₄] (E=Se, R=Me; E=S, R=Et) and diphenyldichalcogenides yielded ligand-exchange products [PPN][PhEFe(CO)₄] (E=Te, Se, S). The compounds [Fe(CO)₃(TePh)(ScPh)₂]^? (l) and [Fe(CO)₃(TePh)₂ (2) crystallize in the isomorphous monoclinic space group C_2/e, with a = 32.035(8), b = 11.708(6), c = 28.909(6) Å, Z = 8, R = 0.048, and R_w = 0.044 (1); with a = 32.089(5), b= 11.745(2), c = 28.990(8) Å, Z = 8, R = 0.048, and R_w = 0.048 (2). The complexes 1 and 2 crystallize as discrete cations of PPN⁺ and anions of [Fe(CO)₃(TcPh)_u(ScPh)_3-n] (n=1, 2), and one half solvent molecule THF. The geometry around Fe(II) is a distorted octahedron with three carbonyl groups and three phenylchalcogenolate ligands occupying facial positions.     

Tetrasilacyclobutadiene ((t)Bu(2)MeSi)(4)Si(4): a new ligand for transition-metal complexes

The anionic complex of [tetrakis(di-tert-butylmethylsilyl) tetrasilacyclobutadiene]dicarbonylcobalt, [(R4Si4)Co(CO)2]-.K+ (R = SiMetBu2) 2-.K+, was synthesized by the reaction of tetrasilacyclobutadiene dianion dipotassium salt [R4Si4]2-.2K+ 1 with an excess of CpCo(CO)2 in THF. X-ray analysis of 2-.[K+(diglyme)2(THF)] showed an almost planar Si4 ring of rectangular shape with an in-plane arrangement of the silyl substituents. 2- was also prepared as a free anion with the [K+[2.2.2]cryptand] counterion by complexation with [2.2.2]cryptand and as a dimer {2-.[K+(THF)3]}2 without complexing reagents in THF. Such a tetrasilacyclobutadiene fragment represents a new type of ligand for Co complexes, being the first example of a cyclobutadiene containing only heavier group 14 elements.     

Übergangsmetall-Silyl-Komplexe, 44. Darstellung der zweikernigen Silyl-Komplexe (CO)3(R3Si)Fe(μ-PR′R′′)Pt(PPh3)2 durch oxidative Addition von (CO)3(R′R′′HP)Fe(H)SiR3 an (C2H4)Pt(PPh3)2

Transition Metal Silyl Complexes, 44. — Preparation of the Binuclear Silyl Complexes (CO)₃(R₃Si)Fe(μ-PR′R′′)Pt(PPh₃)₂ by Oxidative Addition of (CO)₃(R′R′′HP)Fe(H)SiR₃ to (C₂H₄)Pt(PPh₃)₂ The complexes (CO)₃(R′R′′HP)Fe(H)SiR₃ ( 1 ) [PHR′R′′ = PHPh₂, PH₂Ph, PH₂Cy; SiR₃ = SiPh₃, SiPh₂Me, SiPhMe₂, Si(OMe)₃] react with Pt(C₂H₄)(PPh₃)₂ to give the dinuclear, silyl-substituted complexes (CO)₃(R₃Si)Fe(μ-PR′R′′)Pt(PPh₃)₂ ( 2 ) in high yields. Upon reaction of 2 (R = R′ R′′ = Ph) with CO, the PPh₃ ligand at Pt being trans to the PPh₂ bridge is exchanged, and (CO)₃(Ph₃Si)Fe(μ-PPh₂)Pt(PPh₃)CO ( 3 ) is formed. Complex 3 is characterized by an X-ray structure analysis. The rather short Fe — Si distance [233.9(2) pm] and the infrared spectrum of 3 indicate that the Fe — Pt bond is quite polar.     

Highly stereoselective iodolactonization of 4,5-allenoic acids--an efficient synthesis of 5-(1'-iodo-1'(Z)-alkenyl)-4,5-dihydro-2(3H)-furanones

In this paper, it is reported that the efficient iodolactonization of 4,5-allenoic acid with I2 in cyclohexane in the presence or absence of K2CO3 afforded 5-(1'-iodo-1'(Z)-alkenyl)-4,5-dihydro-2(3H)-furanones highly stereoselectively. However, the reaction of axially optically active 4,5-allenoic acids (R)-(-)-5 a and (R)-(-)-5 b with I2 afforded the corresponding products with a serious loss of chirality. This problem was solved by conducting the iodolactonization with N-iodosuccinimide in CH2Cl2 in the presence of Cs2CO3; however, the Z/E selectivity is somewhat lower. The pure optically active Z products were prepared by subsequent kinetic resolution with Sonogashira coupling. The reaction of the substrates with a substituent at the 3-position of the starting 4,5-allenoic acids afforded the trans-4,5-disubstituted gamma-butyrolactones as the only products. The reaction of the 4,5-allenoic acids (S)-(+)-1 l, (R)-(-)-1 l, and (S)-(+)-1 m with a center chirality at the 3-position afforded the trans products with very high enantiopurity and up to 98:2 Z/E selectivity regardless of the axial chirality of the allene moiety.     

多(三甲硅基)取代环戊二烯基二羰基钼环卡宾配合物的合成和结构

三(三甲基硅基)环戊二烯在一缩二乙二醇二甲醚或四氢呋喃中经n-BuLi处理后, 随之与Mo(CO)6加热, 生成相应的环戊二烯基羰基钼负离子锂盐[η^5-{(Me3Si)3C5H5-n}Mo^-(CO)3]Li^+(n=2, 3)(1), 同时观察到有脱硅基现象发生。1与X(CH2)3X在一缩二乙二醇二甲醚中反应, 无论X=I或Br, 均生成标题化合物[X=I: n=3(2), n=2(3); X=Br: n=3(4), n=2(5)]。1与X(CH2)3X的反应如在THF中进行, 则只有当X=I时才能生成环卡宾钼配合物。以元素分析, IR, 1H NMR和13C NMR表征了2-5的结构, 并用X射线衍射测定了4的晶体结构。晶体属单斜晶系,空间群为P21/n, 晶胞参数a=1.2611(3), b=1.2434(2),c=1.7095(6)nm, β=91.07(2)°, V=2.680(2)nm^3,Dc=1.563g.cm^-^3, Z=4, 最终偏差因子R=0.062, Rw=0.054.     

The Synthesis and Structure of (1-(Diphenylphosphino)-1 - (Phenylthio)Ferrocene)Tricarbonyliron(O) (ptppf)Fe(CO)3

The complex (ptppf)Fe(CO)₃ has been prepared in high yield by the reaction of ptppf, l-(diphenyl-phosphino)-l'-(phenylthio)ferrocene, with (cis-cyclooctene)₂-Fe(CO)₃ in THF at ?60°C. The complex has been characterized by IR, ³¹P NMR, mass spectrometry and single-crystal X-ray diffraction. This compound is the first example of a ferrocenyl ligand having both sulfur and phosphorus donor atoms bound to a Fe(CO)₃ moiety. X-ray crystallography shows that the two cyclopentadienyl rings are approximately eclipsed, a rotation of 13° from exactly eclipsed conformation. The tricarbonyl iron center has a trigonal bipyramidal geometry with sulfur occupying the equatorial site and phosphorus the axial site. Crystals of (ptppf)Fe(CO)₃ are monoclinic, with a = 11.645(2), b = 14.304(1), c = 17.075(2) Å,β = 109.23(3)°, Z = 4, and space group P 2₁/n. The structure was solved according to the heavy-atom method and refined by full-matrix least-squares procedures to R = 0.037 for 2098 reflections with I ≥ 2.5σ(I).     

Reactions of [Et(4)N](3)[Sb{Fe(CO)(4)}(4)] with Alkyl Halides and Dihalides: Formation of the Alkyl- and the Dialkylantimony-Iron Carbonyl Complexes

The reactions of [Et(4)N](3)[Sb{Fe(CO)(4)}(4)] (1) with RX (R = Me, Et, n-Pr; X = I) in MeCN form the monoalkylated antimony complexes [Et(4)N](2)[RSb{Fe(CO)(4)}(3)] (R = Me, 2; R = Et, 4; R = n-Pr, 6) and the dialkylated antimony clusters [Et(4)N][R(2)Sb{Fe(CO)(4)}(2)] (R = Me, 3; R = Et, 5; R = n-Pr, 7), respectively. When [Et(4)N](3)[Sb{Fe(CO)(4)}(4)] reacts with i-PrI, only the monoalkylated antimony complex [Et(4)N](2)[i-PrSb{Fe(CO)(4)}(3)] (8) is obtained. The mixed dialkylantimony complex [Et(4)N][MeEtSb{Fe(CO)(4)}(2)] (9) also can be synthesized from the reaction of 2 with EtI. While the reaction with Br(CH(2))(2)Br produces [Et(4)N](2)[BrSb{Fe(CO)(4)}(3)] (10), treatment with Cl(CH(2))(3)Br forms the monoalkylated product [Et(4)N](2)[Cl(CH(2))(3)Sb{Fe(CO)(4)}(3)] (11) and a dialkylated novel antimony-iron complex [Et(4)N][{&mgr;-(CH(2))(3)}Sb{Fe(CO)(4)}(3)] (12). On the other hand, the reaction with Br(CH(2))(4)Br forms the monoalkylated antimony product and the dialkylated antimony complex [Et(4)N][{&mgr;-(CH(2))(4)}Sb{Fe(CO)(4)}(2)] (13). Complexes 2-13 are characterized by spectroscopic methods or/and X-ray analyses. On the basis of these analyses, the core of the monoalkyl clusters consists of a central antimony atom tetrahedrally bonded to one alkyl group and three Fe(CO)(4) fragments and the dialkyl products are structurally similar to the monoalkyl clusters, with the central antimony bonded to two alkyl groups and two Fe(CO)(4) moieties in each case. The dialkyl complex 3 crystallizes in the monoclinic space group P2(1)/c with a = 13.014(8) ?, b = 11.527(8) ?, c = 17.085(5) ?, beta = 105.04(3) degrees, V = 2475(2) ?(3), and Z = 4. Crystals of 12 are orthorhombic, of space group Pbca, with a = 14.791(4) ?, b = 15.555(4) ?, c = 27.118(8) ?, V = 6239(3) ?(3), and Z = 8. The anion of cluster 12 exhibits a central antimony atom bonded to three Fe(CO)(4) fragments with a -(CH(2))(3)- group bridging between the Sb atom and one Fe(CO)(4) fragment. This paper discusses the details of the reactions of [Et(4)N](3)[Sb{Fe(CO)(4)}(4)] with a series of alkyl halides and dihalides. These reactions basically proceed via a novel double-alkylation pathway, and this facile methodology can as well provide a convenient route to a series of alkylated antimony-iron carbonyl clusters.     

钼铁混合金属原子簇的研究Ⅱ(η~5-C_5H_5)_2M_(o2)F_(e2)(μ_3-T_e)_2(μ_3-CO)-(μ_2-CO)(CO)_5的合成及结构

钼铁混合金属原子簇Mo_2Fe_2Te_2(CO)_7(η~5-C_5H_5)_2是Fe_3Te_2(CO)_9与Mo_2(CO)_6(η~5～C_5H_5)_2反应所得的产物之一。它的晶体属正交晶系,空间群为Pbn2_1。晶胞参数:a=12.172(5);b=13.595(2);c=12.924(4)A,V=2138.5(2)A~3。晶体结构由直接法及差值Fourier合成解出,经最小二乘法修正,最终R因子为0.030(3233个Ⅰ>26(Ⅰ)的反射)。在簇分子中,四个金属原子呈四面体构型,两个μ_8-Te原子和一个不对称的μ_8-CO分别桥连到四面体的三个三角面的金属原子上,从而构成了缺顶点的类立方烷结构。     

Synthesis and Characterization of nido-[1,1,2,2-(CO)(4)-1,2-(PPh(3))(2)-1,2-FeIrB(2)H(5)]: A Heterobimetallaborane Analogue of nido-[B(4)H(7)](-)

The synthesis and characterization of nido-[1,1,2,2-(CO)(4)-1,2-(PPh(3))(2)-1,2-FeIrB(2)H(5)] (1) is reported. 1 is formed in low yield as a degradation product from the reaction between [{&mgr;-Fe(CO)(4)}B(6)H(9)](-) and trans-Ir(CO)Cl(PPh(3))(2) in THF and is characterized from NMR, IR, and analytical data and by a single-crystal X-ray diffraction study. 1 crystallizes in the monoclinic space group P2(1)/n with a = 12.8622(12), b = 14.3313(12), c = 23.579(3) ?, beta = 97.12(2) degrees, Z = 4, V = 4257.0(8) ?(3), R(1) = 4.83%, and wR(2)()(F(2)) = 12.43%. The heterobimetallaborane structure may be viewed as a derivative of the binary boron hydride nido-[B(4)H(7)](-) and is related to the known homobimetallatetraborane analogues [Fe(2)(CO)(6)B(2)H(6)] and [Co(2)(CO)(6)B(2)H(4)]. 1 exhibits proton fluxionality in its (1)H NMR spectrum, which is related to that found in the latter two compounds.     

Insertion reactions of hydridonitrosyltetrakis(trimethylphosphine) tungsten(0)

[W(H)(NO)(PMe3)4] (1) was prepared by the reaction of [W(Cl)(NO)(PMe3)4] with NaBH4 in the presence of PMe3. The insertion of acetophenone, benzophenone and acetone into the W-H bond of 1 afforded the corresponding alkoxide complexes [W(NO)(PMe3)4(OCHR1R2)](R1 = R2 = Me (2); R1 = Me, R2 = Ph (3); R1 = R2 = Ph (4)), which were however thermally unstable. Insertion of CO2 into the W-H bond of yields the formato-O complex trans-W(NO)(OCHO)(PMe3)4 (5). Reaction of trans-W(NO)(H)(PMe3)4 with CO led to the formation of mer-W(CO)(NO)(H)(PMe3)3 (6) and not the formyl complex W(NO)(CHO)(PMe3)4. Insertion of Fe(CO)(5), Re2(CO)10 and Mn2(CO)10 into trans-W(NO)(H)(PMe3)4 resulted in the formation of trans-W(NO)(PMe3)4(mu-OCH)Fe(CO)4 (7), trans-W(NO)(PMe3)4(mu-OCH)Re2(CO)9 (8) and trans-W(NO)(PMe3)4(mu-OCH)Mn2(CO)9 (9). For Re2(CO)10, an equilibrium was established and the thermodynamic data of the equilibrium reaction have been determined by a variable-temperature NMR experiments (K(298K)= 104 L mol(-1), DeltaH=-37 kJ mol(-1), DeltaS =-86 J K(-1) mol(-1)). Both compounds 7 and 8 were separated in analytically pure form. Complex 9 decomposed slowly into some yet unidentified compounds at room temperature. Insertion of imines into the W-H bond of 1 was also additionally studied. For the reactions of the imines PhCH=NPh, Ph(Me)C=NPh, C6H5CH=NCH2C6H5, and (C6H5)2C=NH with only decomposition products were observed. However, the insertion of C10H7N=CHC6H5 into the W-H bond of led to loss of one PMe3 ligand and at the same time a strong agostic interaction (C17-H...W), which was followed by an oxidative addition of the C-H bond to the tungsten center giving the complex [W(NO)(H)(PMe3)3(C10H6NCH2Ph)] (10). The structures of compounds 1, 4, 7, 8 and 10 were studied by single-crystal X-ray diffraction.     

Syntheses of highly unsaturated isocyanides via organometallic pathways

The carbon carbon coupling reaction by nucleophilic attack of (CO)(5)Cr(CN-CF=CF(2)) 1 by lithium or Grignard compounds 2a-i yields the isocyanide complexes (CO)(5)Cr(CN-CF=CF-R) 3a-i (a R = CH=CH(2), b R = CH=CF(2), c R = C≡CH, d R = C≡C-SiMe(3), e R = C≡C-Ph, f R = C≡C-C(6)F(4)OMe, g R = C≡C-C(6)H(3)(CF(3))(2), h R = C(6)F(5), i R = C(6)H(3)(CF(3))(2)) as mixtures of E and Z isomers. The dinuclear complexes 5a-c are obtained from the reaction of 1 with the dilithio or dimagnesium compound 4a-c as the Z,Z-, E,Z- and E,E-isomers, respectively. (CO)(5)Cr(CN-CF=CF-C≡C-C≡C-CF=CF-NC)Cr(CO)(5)7 is obtained as a mixture of Z,Z-, Z,E- and E,E-isomers from (CO)(5)Cr(CN-CF=CF-C≡C-H 3d by Eglington-Glaser coupling. (CO)(5)Cr(CN-CF=CF-C≡C-CF=CF-NC)Cr(CO)(5)6 and (CO)(5)Cr(CN-CF=CF-C=C-C≡C-CF=CF-NC)Cr(CO)(5)7 react with octacarbonyldicobalt forming the cluster compounds Z,Z-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-CF=CF-NC)Cr(CO)(5)}Co(2)(CO)(6)] Z,Z-8, E,Z-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-CF=CF-NC)Cr(CO)(5)}Co(2)(CO)(6)] E,Z-8 and E,E-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-CF=CF-NC)Cr(CO)(5)}Co(2)(CO)(6)] E,E-8 and Z,Z-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-C≡C-CF=CF-NC)Cr(CO)(5)}{Co(2)(CO)(6)}(2)] Z,Z-9, E,Z-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-C≡C-CF=CF-NC)Cr(CO)(5)}{Co(2)(CO)(6)}(2)] E,Z-9 and E,E-[{η(2)-μ(2)-(CO)(5)Cr(CN-CF=CF-C≡C-C≡C-CF=CF-NC)Cr(CO)(5)}{Co(2)(CO)(6)}(2)] Z,Z-9, respectively. The crystal and molecular structures of E-3d, Z-3h, Z,Z-8, E,Z-8 and Z,Z-9 were elucidated by single-crystal X-ray crystallography.     

C-C coupling reactions in the coordination sphere of rhodium(I) and rhodium(III): New routes for the di- and trimerization of terminal alkynes

The alkynyl(vinylidene)rhodium(I) complexes trans-[Rh(C[triple bond, length as m-dash]CR)(=C=CHR)(PiPr3)2] 2, 5, 6 react with CO by migratory insertion to give stereoselectively the butenynyl compounds trans-[Rh{eta1-(Z)-C(=CHR)C[triple bond, length as m-dash]CR}(CO)(PiPr3)2](Z)-7-9, of which (Z)-7 (R=Ph) and (Z)-8 (R=tBu) rearrange upon heating or UV irradiation to the (E) isomers. Similarly, trans-[Rh{eta1-C(=CH2)C[triple bond, length as m-dash]CPh}(CO)(PiPr3)2] 12 and trans-[Rh{eta1-(Z)-C(=CHCO2Me)C[triple bond, length as m-dash]CR}(CO)(PiPr3)2](Z)-15, (Z)-16 have been prepared. At room temperature, the corresponding "non-substituted" derivative trans-[Rh{eta1-C(=CH2)C[triple bond, length as m-dash]CH}(CO)(PiPr3)2] 18 is in equilibrium with the butatrienyl isomer trans-[Rh(eta1-CH=]C=C=CH2)(CO)(PiPr3)2] 19 that rearranges photochemically to the alkynyl complex trans-[Rh(C[triple bond, length as m-dash]CCH=CH2)(CO)(PiPr3)2] 20. Reactions of (Z)-7, (E)-7, (Z)-8 and (E)-8 with carboxylic acids R'CO2H (R'=CH3, CF3) yield either the butenyne (Z)- and/or (E)-RC[triple bond, length as m-dash]CCH=CHR or a mixture of the butenyne and the isomeric butatriene, the ratio of which depends on both R and R'. Treatment of 2 (R=Ph) with HCl at -40 degrees C affords five-coordinate [RhCl(C[triple bond, length as m-dash]CPh){(Z)-CH=CHPh}(PiPr3)2] 23, which at room temperature reacts by C-C coupling to give trans-[RhCl{eta2-(Z)-PhC[triple bond, length as m-dash]CCH=CHPh}(PiPr3)2](Z)-21. The related compound trans-[RhCl(eta2-HC[triple bond, length as m-dash]CCH=CH2)(PiPr3)2] 27, prepared from trans-[Rh(C[triple bond, length as m-dash]CH)(=C=CH2)(PiPr3)2] 17 and HCl, rearranges to the vinylvinylidene isomer trans-[RhCl(=C=CHCH=CH2)(PiPr3)2] 28. While stepwise reaction of 2with CF3CO2H yields, via alkynyl(vinyl)rhodium(III) intermediates (Z)-29 and (E)-29, the alkyne complexes trans-[Rh(kappa1-O2CCF3)(eta2-PhC[triple bond, length as m-dash]CCH=CHPh)(PiPr3)2](Z)-30 and (E)-30, from 2 and CH3CO2H the acetato derivative [Rh(kappa2-O2CCH3)(PiPr3)2] 33 and (Z)-PhC[triple bond, length as m-dash]CCH=]CHPh are obtained. From 6 (R=CO2Me) and HCl or HC[triple bond, length as m-dash]CCO2Me the chelate complexes [RhX(C[triple bond, length as m-dash]CCO2Me){kappa2(C,O)-CH=CHC(OMe)=O}(PiPr3)2] 34 (X=Cl) and 35 (X=C[triple bond, length as m-dash]CCO2Me) have been prepared. In contrast to the reactions of [Rh(kappa2-O2CCH3)(C[triple bond, length as m-dash]CE)(CH=CHE)(PiPr3)2] 37(E=CO2Me) with chloride sources which give, via intramolecular C-C coupling, four-coordinate trans-[RhCl{eta2-(E)-EC[triple bond, length as m-dash]CCH=CHE}(PiPr3)2](E)-36, treatment of 37with HC[triple bond, length as m-dash]CE affords, via insertion of the alkyne into the rhodium-vinyl bond, six-coordinate [Rh(kappa2-O2CCH3)(C[triple bond, length as m-dash]CE){eta1-(E,E)-C(=CHE)CH=CHE}(PiPr3)2] 38. The latter reacts with MgCl2 to yield trans-[RhCl{eta2-(E,E)-EC[triple bond, length as m-dash]CC(=CHE)CH=CHE}(PiPr3)2] 39, which, in the presence of CO, generates the substituted hexadienyne (E,E)-EC[triple bond, length as m-dash]CC(=CHE)CH=CHE 40.     

新型硅基桥连双(环戊二烯基)四羰基二铁类配合物的合成

以六甲基二硅烷为原料,经氯代、格式反应和锂化反应制得双(环戊二烯基)配体(C5H5)2MeSiSiMe2R(3a^3c),将该配体分别与五羰基铁在对二甲苯中回流反应,合成了3种新型的硅基桥连双(环戊二烯基)四羰基二铁类配合物[η^5,η^5-C5H4MeSi(SiMe2R)C5H4]Fe2(CO)2(μ-CO)2[R=p-C6H4CH3(4a),R=p-C6H4OCH3(4b),R=CH2C6H5(4c)],其结构经1H NMR,13C NMR,IR和元素分析表征。并用X-射线单晶衍射法确定了配合物4b的分子结构。结果表明:4b(CCDC:1942618)属单斜晶系,Cc空间群,晶胞参数a=18.591(3)A,b=10.3080(10)A,c=14.136(2)A,α=90°,β=117.262(6)°,γ=90°,V=2408.1(6)A^3,Z=4,F(000)=1152,Dc=1.546 g·cm^-3,μ=1.338 mm^-1,R1=0.0351,wR2=0.0754。     

An Approach to Heterometallic Complexes with Selenolate and Tellurolate Ligands: Crystal Structures of cis-[Mn(CO)(4)(SePh)(2)](-), [(CO)(3)Mn(&mgr;-SeMe)(3)Mn(CO)(3)](-), (CO)(4)Mn(&mgr;-TePh)(2)Co(CO)(&mgr;-SePh)(3)Mn(CO)(3), and (CO)(3)Mn(&mgr;-SePh)(3)Fe(CO)(3)

Oxidative addition of diorganyl diselenides to the coordinatively unsaturated, low-valent transition-metal-carbonyl fragment [Mn(CO)(5)](-) produced cis-[Mn(CO)(4)(SeR)(2)](-). The complex cis-[PPN][Mn(CO)(4)(SePh)(2)] crystallized in triclinic space group P&onemacr; with a = 10.892(8) ?, b = 10.992(7) ?, c = 27.021(4) ?, alpha = 101.93(4) degrees, beta = 89.79(5) degrees, gamma = 116.94(5) degrees, V = 2807(3) ?(3), and Z = 2; final R = 0.085 and R(w) = 0.094. Thermolytic transformation of cis-[Mn(CO)(4)(SeMe)(2)](-) to [(CO)(3)Mn(&mgr;-SeMe)(3)Mn(CO)(3)](-) was accomplished in high yield in THF at room temperature. Crystal data for [Na-18-crown-6-ether][(CO)(3)Mn(&mgr;-SeMe)(3)Mn(CO)(3)]: trigonal space group R&thremacr;, a = 13.533(3) ?, c = 32.292(8) ?, V = 5122(2) ?(3), Z = 6, R = 0.042, R(w) = 0.041. Oxidation of Co(2+) to Co(3+) by diphenyl diselenide in the presence of chelating metallo ligands cis-[Mn(CO)(4)(SePh)(2)](-) and cis-[Mn(CO)(4)(TePh)(2)](-), followed by a bezenselenolate ligand rearranging to bridge two metals and a labile carbonyl shift from Mn to Co, led directly to [(CO)(4)Mn(&mgr;-TePh)(2)Co(CO)(&mgr;-SePh)(3)Mn(CO)(3)]. Crystal data: triclinic space group P&onemacr;, a = 11.712(3) ?, b = 12.197(3) ?, c = 15.754(3) ?, alpha = 83.56(2) degrees, beta = 76.13(2) degrees, gamma = 72.69(2) degrees, V = 2083.8(7) ?(3), Z = 2, R = 0.040, R(w) = 0.040. Addition of fac-[Fe(CO)(3)(SePh)(3)](-) to fac-[Mn(CO)(3)(CH(3)CN)(3)](+) resulted in formation of (CO)(3)Mn(&mgr;-SePh)(3)Fe(CO)(3). This neutral heterometallic complex crystallized in monoclinic space group P2(1)/n with a = 8.707(2) ?, b = 17.413(4) ?, c = 17.541(4) ?, beta = 99.72(2) degrees, V = 2621(1) ?(3), and Z = 4; final R = 0.033 and R(w) = 0.030.     

Syntheses of chromium pentacarbonyl derivatives of arsenic(V) and antimony(V). contrasting chemical reactivity with organic halogen derivatives

We have synthesized a new series of chromium-group 15 dihydride and hydride complexes [H(2)As(Cr(CO)(5))(2)](-) (1) and [HE(Cr(CO)(5))(3)](2)(-) (E = As, 2a; E = Sb, 2b), which represent the first examples of group 6 complexes containing E-H fragments. The contrasting chemical reactivity of 2a and 2b with organic halogen derivatives is demonstrated. The reaction of 2a with RBr (R = PhCH(2), HC triple bond CCH(2)) produces the RX addition products [(R)(Br)As(Cr(CO)(5))(2)](-) (R = PhCH(2), 3; R = C(3)H(3), 4), while the treatment of 2b with RX (RX = PhCH(2)Br or HC triple bond CCH(2)Br, CH(3)(CH(2))(5)C(O)Cl) forms the halo-substituted complexes [XSb(Cr(CO)(5))(3)](2-) (X = Br, 5; X = Cl, 6). Moreover, the dihaloantimony complexes [XX'Sb(Cr(CO)(5))(2)](-) can be obtained from the reaction of 2b with the appropriate organic halides. In this study, a series of organoarsenic and antimony chromium carbonyl complexes have been synthesized and structurally characterized and the role of the main group on the formation of the resultant complexes is also discussed.     

Die Strukturen der 1,3,5-Trisilacyclohexan-Eisendicarbonyl-cyclopentadienylkomplexe C3H6Si3Cl5Fe(CO)2πcp und C3H6Si3Cl4(Fe(CO)2πcp)2

Structures of the l,3,5-Trisilacyclohexane-Iron Dicarbonyl-cyclopentadienyl Complexes and C₃H₆Si₃Cl₅Fe(CO)₂πcp and C₃H₆Si₃Cl₄(Fe(CO₂)πcp)₂ Trisilapentachlorocyclo-hexyl-dicarbonylcyclopentadienyliron C₃H₆Si₃Cl₅Fe(CO)₂πcp 1 and Trisilatetrachlorocyclohexyl-bis(dicarboncyclopentadienyliron)C₃H₆Si₃Cl₄(Fe(CO)₂πcp)₂ 2 are 1,3,5-Trisilacyclohexane complexes substituted by dicarbonylcyclopentadienyliron at one and two silicon atoms of the six-membered ring, respectively. The crystal and molecular structures were determined from single crystals ( 1 ; space group P2₁/a (No. 14); a = 1100.5 pm; b = 2033.9 pm; c = 843.3pm; β = 98.58°; Z = 4; MoKα-radiation; 3142h k l; R = 0.036. 2 ; space group P1 ; (No. 2); a = 1231.1 pm; b = 1267.3 pm; c = 1045.9 pm; α = 113.23°; β = 83.93°; γ = 115.00°; Z = 2; Mokα-radiation; 4196 h k 1; R = 0.065). In both complexes the six-membered rings of the carbosilane ligands are in skew-boat conformation. The bond lengths Fe? Si are 226.4 pm and 228.1 pm, respectively. The distances Si? C and Si? Cl are 186 pm and 206 pm in 1 and 187 pm and 209 pm in 2 . Their different lengths depend on the position in the ligand system and can be explained with the concept of bond orders.