Regioselectivity of the addition of ?CCl3 and ?But radicals to (η2-C70)[Os(CO)(PPh3)2(CNBut)]n (n = 1, 2): an ESR study

The addition of ^•CCl₃ and ^•Bu^t radicals to (η²-C₇₀)Os(CO)(PPh₃)₂(CNBu^t) (1) and (η²-C₇₀)[Os(CO)(PPh₃)₂(CNBu^t)]₂ (3) was studied by ESR spectroscopy. The metal fragment in complex 1 does not influence the regioselectivity of the addition of the radicals to it. The stability of the spin adducts formed upon addition of free radicals to complexes 1 and 3 is mainly governed by delocalization of the unpaired electron over three hexagonal rings.     

The structurally characterised silyl complexes, Os(κ-S2CNMe2)(SiMeCl2)(CO)(PPh3)2 and Os(κ-S2CNMe2)(SiCl3)(CO)(PPh3)2, which have remarkably unreactive Si-Cl bonds

Treatment of Os(κ²-S₂CNMe₂)H(CO)(PPh₃)₂ with HSiMeCl₂ or HSiCl₃ gives in high yield Os(κ²-S₂CNMe₂)(SiMeCl₂)(CO)(PPh₃)₂ (1) or Os(κ²-S₂CNMe₂)(SiCl₃)(CO)(PPh₃)₂ (2), respectively. The crystal structures of both compounds have been determined and the Os-Si distances are 2.3672(10) Å for 1 and 2.3449(12) Å for 2. In solution, and under forcing conditions, both compounds are extraordinarily unreactive towards hydroxide ions.     

Thiolate-bridged heterometallic complexes of manganese and platinum: Synthesis and molecular structures of (CO)4Mn(μ-SPh)Pt(PPh3)2, (CO)3(PPh3)Mn(μ-SPh)Pt(PPh3)(CO), and (CO)3Mn(μ-SPh)Pt(PPh3)(Dppm)

A reaction of the dimer [Mn(CO)₄(SPh)]₂ with (PPh₃)₂Pt(C₂Ph₂) gave the heterometallic complex (CO)₄Mn(μ-SPh)Pt(PPh₃)₂ (I) and its isomer (CO)₃(PPh₃)Mn(μ-SPh)Pt(PPh₃)(CO) (II). A reaction of complex I with a diphosphine ligand (Dppm) yielded the heterometallic complex (CO)₃Mn(μ-SPh)Pt(PPh₃)(Dppm) (III). Complexes I–III were characterized by X-ray diffraction. In complex I, the single Mn-Pt bond (2.6946(3) ?) is supplemented with a thiolate bridge with the shortened Pt-S and Mn-S bonds (2.3129(5) and 2.2900(6) ?, respectively). Unlike complex I, in complex II, one phosphine group at the Pt atom is exchanged for one CO group at the Mn atom. The Mn-Pt bond (2.633(1) ?) and the thiolate bridge (Pt-S, 2.332(2) ?; Mn-S, 2.291(2) ?) are retained. In complex III, the Mn-Pt bond (2.623(1) ?) is supplemented with thiolate (Pt-S, 2.341(2) ?; Mn-S, 2.292(2) 0?) and Dppm bridges (Pt-P, 2.240(1)?; Mn-P, 2.245(2) ?). Apparently, the Pt atom in complexes I–III is attached to the formally double bond , as in Pt complexes with olefins.     

X-ray and conformation analysis of the new trinuclear cluster of osmium Os3(μ,η2-OCC6H5)(η3-C3H5)(CO)9

The crystal structure of the Os₃(μ,η²-O=CC₆H₅)(η³-C₃H₅)(CO)₉ cluster synthesized by the reaction of the (μ-H)Os₃(μ-O=CC₆H₅)(CO)₁₀ complex with allylamine in chloroform was determined by X-ray analysis. Prolonged storage of the reaction mixture led to N-C bond cleavage in allylamine and η³-addition of the allyl fragment at one of the Os atoms (Os-C 2.246 ?, 2.248 ?, and 2.273 ?). The unit cell parameters of the complex are a = 9.494(1) ?, b = 10.479(1) ?, c = 12.474(2) ?, α = 84.55(1)°, β = 70.08(1)°, γ = 70.72(1)°, V = 1255.8(4), ?³, space group P , Z = 2; C₁₉H₁₀O₁₀Os₃; d _calc = 2.922 g/cm³, 3085 I _hkl > 2σ _I of 3611 collected reflections; R = 0.0252. The structure of Os₃(μ,η²-O=CC₆H₅)(η³-C₃H₅)(CO)₉ is molecular. The plane of the Os₃ triangle and the OsCOOs plane are connected according to the “butterfly” principle with an angle of 103.4° between them. The Os-Os distances in the cluster core vary from 2.836(1) ? to 2.844(1) ?; the Os-C_carb distances are 1.88(1)–1.97(1) ?; the distances to the atoms of the bridging ligands are Os-C 2.11(1) ?, Os-O 2.14(1) ?; the O-C bridging bond is 1.24(1) ?. of the Os₃(μ,η²-O=CC₆H₅)(η³-C₃H₅)(CO)₉ triosmium cluster were studied theoretically. The potential curve of the internal rotation of the allyl ligand relative to the Os(1)-C(9) bond was determined. The rotation barrier of the allyl ligand in crystal relative to the Os(1)-C(9) bond is 8.38 kJ/mol, and the rotation of the ligand is not hindered. The effects of the intra-and intermolecular interactions on the conformation state of the cluster complex are considered. Original Russian Text Copyright ? 2008 by V. A. Maksakov, N. V. Pervukhina, N. V. Podberezskaya, M. Yu. Afonin, V. A. Potemkin, and V. P. Kirin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 5, pp. 926–932, September–October, 2008.     

簇合物Co3(CO)7(μ3-S)[μ,η2-CNP(S)(C6H4OCH3)OC(Ph)CH]和Co3(CO)7(μ3-S)[μ,η2-SCNC(CH3)2P(S)(Cl)N(Ph)]的合成与晶体结构

用Co₂(CO)₈分别与两个杂环配体C(S)NHP(S)(C₆H₄OCH₃)OC(Ph)CH (L₁)和C(S)NHC(CH₃)₂P(S)(Cl)N(Ph) (L₂)反应,合成两个新的三核钴羰基硫簇合物Co₃(CO)₇(μ₃-S)[μ,η²-CNP(S)(C₆H₄OCH₃)OC(Ph)CH](Ⅰ)和Co₃(CO)₇(μ₃-S)[μ,η²-SCNC(CH₃)₂P(S)(Cl)N(Ph)](Ⅱ)。用元素分析,IR, ¹H NMR, ³¹P NMR及MS谱表征了它们的结构,同时用X射线衍射法测定了它们的晶体分子结构,二者属于三斜晶系,空间群P1,Ⅰ的晶胞参数为:a=0.84768(1)nm,b=1.19049(3)nm,c=1.43639(1)nm,α=86.926(1)°,β=81.601(3)°,γ=88.535(2)°,V=1.4318(5)nm³,Z=2,D_c=1.641g·cm^-3,F(000)=716,μ=1.893mm^-1,R=0.0602,R_w=0.1515。Ⅱ的晶胞参数为:a=1.2050(2)nm,b=1.2448(2)nm,c=0.8951(2)nm,α=97.49(1)°,β=93.552(4)°,γ=108.432(3)°,V=1.2554(3)nm³,Z=2,D_c=1.841g·cm^-3,F(000)=690,μ=2.419mm^-1,R=0.0423,R_w=0.1075。Ⅰ和Ⅱ的分子骨架Co3S为三角锥构型,S作为面桥基配体,所有CO作为端基配体与三个Co原子成键。Ⅰ中含有CoCoCN四元环组件,Ⅱ中含有CoCoSCN五元环组件。     

Soft activation of the C-S bond: X-ray diffraction and spectroscopic study of the cluster Ru4(μ4-S)(μ,η3-C3H5)2(CO)12

The complex Ru₄(μ₄-S)(μ,η³-C₃H₅)₂(CO)₁₂ is prepared and examined by IR and NMR spectroscopy; its crystal structure is determined (an automatic Bruker-Nonius X8 Apex four-circle diffractometer equipped with a 2-D CCD-detector, 100 K, graphite-monochromated molybdenum source, λ = 0.71073 ?). The crystal belongs to the orthorhombic crystal system with unit cell parameters a = 19.3781(9) ?, b = 12.2898(7) ?, c = 10.1726(4) ?, V = 2422.6(2) ?³, space group Pnma, Z = 4, composition C₁₈H₁₀O₁₂Ru₄S, d _x = 2.343 g/cm³. The molecule of point symmetry C ₁ is situated on the mirror plane of the space group Pnma, two carbonyl groups at Ru2 and Ru3 atoms overlapping with the allylic ligand with a weight of 50% so that carbon atoms coincide. Thus, we have a racemic structure with two overlapping enantiomers of the molecule of Ru₄(μ₄-S)(μ,η³-C₃H₅)₂(CO)₁₂. Original Russian Text Copyright ? 2008 by I. Yu. Prikhod’ko, V. P. Kirin, V. A. Maksakov, A. V. Virovets, and A. V. Golovin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 49, No. 4, pp. 748–752, May–June, 2008.     

配合物{(n-Bu)2Sn[(η5-C5H5)Fe(η5-C5H4)COO]2}2的合成、谱学表征及晶体结构

合成了新型配合物{(n-Bu)₂Sn[(η⁵-C₅H₅)Fe(η⁵-C₅H₄)COO]₂}₂，用元素分析、红外光谱和核磁共振谱( ¹H、¹³C、¹¹⁹Sn)进行了表征，并用X-射线单晶衍射分析法测定其晶体结构。晶体属单斜晶系，空间群P2₁/c，晶胞参数a=11.753(4)?，b=21.133(7)?，c=23.374(9)?，β=101.62(3)°，V=5687(4)?³，Z=4，D_c=1.614Mg·m^-3，μ(MoKα)=1.912mm^-1，F(000)=2800，最终可靠因子R₁=0.0827，wR₂=0.2085。配合物分子呈中心对称，是具有Sn₂O₂中心内环的二聚体结构;每个锡原子与5个O原子和2个C原子形成扭曲的五角双锥几何构型，其中5个O原子为赤道配位原子，而C-Sn-C为配合物的轴。     

Dynamic behavior of [(η-C5H4CH3)Cr(CO)2(μ-SBu)Pt(PPh3)2] in solution

The structure and dynamic behavior of complex [(η⁵-C₅H₄CH₃)Cr(CO)₂(μ-SBu)Pt(PPh₃)₂] in solution was studied by multinuclear (¹H, ¹³C, ³¹P) NMR spectroscopy including a phase-sensitive NOESY experiment. Increasing temperature causes rupture of the Cr-Pt bond in the three-membered ring of the complex and rotation of the S-Pt(PPh₃)₂ unit around the Cr-S bond line, followed by formation of a new Cr-Pt bond to close the ring. All activation parameters for this dynamic process have been determined.     

簇合物[(η5-C5Me5)WS3{Cu(PPh3)}3Cl](PF6)的合成及晶体结构

Reaction of a preformed cluster [{(η⁵-C₅Me₅)WS₃}₃Cu₇(MeCN)₉](PF₆)₄ (1) in MeCN with LiCl and PPh₃ gave rise to a tetranuclear cationic cluster [(η⁵-C₅Me₅)WS₃{Cu(PPh₃)}₃Cl](PF₆) (2). The title compound 2 was characterized by elementary analysis, IR, UV-Vis, ¹H NMR, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P2₁/c with a=1.799 8(4) nm, b=2.083 6(4) nm, c=1.913 5(4) nm, β=113.63(3)°, V=6.574(3) nm³, Z=4. The cluster cation [(η⁵-C₅Me₅)WS₃{Cu(PPh₃)}₃Cl]⁺ of 2 contains a strongly distorted, cubane-like structure [WS₃Cu₃Cl] in which one Cl weakly fills into the void of the nido-like [WS₃Cu₃] fragment with three relatively long Cu-Cl distances. CCDC: 270415.     

含硅铁键环状化合物[Me2Si-η5-C5H4Fe(CO)(PPh3)][Me2Si-η5-C5H4Fe- (CO)2－n(PPh3)n] (n＝0或1)的合成与结构

鉴于含硅-过渡金属键化合物作为催化剂具有重要的应用价值, 在我们最近发现的化合物(η⁵,η⁵-C₅H₄Me₂SiSi-Me₂C₅H₄)Fe₂(CO)₄ (1)的硅硅键和铁铁键复分解重排反应可以有效地合成含有两个硅铁键的环状化合物[Me₂Si-η⁵-C₅H₄- Fe(CO)₂]₂ (2)的基础上, 对该硅铁键环状化合物的三苯基膦取代衍生物[Me₂Si-η⁵-C₅H₄-Fe(CO)(PPh₃)][Me₂Si-η⁵-C₅H₄Fe(CO)_2－n(PPh₃)_n] (3: n＝0, 5: n＝1)的合成方法进行了研究. 发现化合物1在三苯基膦存在下的复分解重排反应是合成单三苯基膦取代产物3的最好方法; 而双三苯基膦取代化合物5则可通过光照条件下2与三苯基膦发生羰基取代反应而得到, 产物中含有的顺反异构体可利用制备薄层色谱法分离. 利用X射线衍射法测定了化合物3的分子结构, 考察了三苯基膦配体的存在对分子结构的影响以及三苯基膦与铁形成的配位键的稳定性.     

Some complexes containing Pt-C5-Co3 fragments: Molecular structure of trans-Pt{CCCC-μ3-C[Co3(μ-dppm)(CO)6(PPh3)]}2(PPh3)2 determined using synchrotron radiation

Reactions of platinum(II) chloro-phosphine complexes with Co₃(μ₃-CCCCCSiMe₃)(μ-dppm)(CO)₇ in the presence of NaOMe have given the compounds Pt{CCCC-μ₃-C[Co₃(μ-dppm)(CO)₇]}₂(dppe) (1), trans-Pt{CCCC-μ₃-C[Co₃(μ-dppm)(CO)₇]}₂(PEt₃)₂ (2) and trans-Pt{CCCC-μ₃-C[Co₃(μ-dppm) (CO)₆(PPh₃)]}₂(PPh₃)₂ (3), each of which contains two Co₃ clusters linked by C₅ chains to the Pt centre. Electrochemical studies (CVs) show the presence of both oxidation and reduction processes, the latter probably occurring on the CCo₃ cores. Ready reductive elimination of {Co₃(μ-dppm)(CO)₇}₂(μ₃:μ₃-C₁₀) occurs from 1 upon heating. The X-ray study of 3 was carried out using synchrotron radiation (Advanced Photon Source, Argonne, IL) to confirm its structure.     

Unsaturation in binuclear cyclopentadienylchromium carbonyl thiocarbonyls: Viability of (η-C5H5)2Cr2(CS)2(CO)3 in contrast to (η-C5H5)2Cr2(CO)5

The cyclopentadienylchromium carbonyl thiocarbonyls Cp₂Cr₂(CS)₂(CO)_n (n = 4, 3, 2, 1) have been studied by density functional theory using the B3LYP and BP86 functionals. The lowest energy Cp₂Cr₂(CS)₂(CO)₄ structure can be derived from the experimentally characterized unbridged Cp₂Cr₂(CO)₆ structure by replacing the two terminal carbonyl groups furthest from the Cr-Cr bond with two terminal CS groups. The two lowest energy Cp₂Cr₂(CS)₂(CO)₃ structures have a single four-electron donor η²-μ-CS group and a formal Cr-Cr single bond of length ∼3.1 Å. In contrast to the carbonyl analogue Cp₂Cr₂(CO)₅ these Cp₂Cr₂(CS)₂(CO)₃ structures are viable with respect to disproportionation into Cp₂Cr₂(CS)₂(CO)₄ and Cp₂Cr₂(CS)₂(CO)₂ and thus are promising synthetic targets. The lowest energy Cp₂Cr₂(CS)₂(CO)₂ structures have all two-electron donor CO and CS groups and short CrCr distances around ∼2.3 Å suggesting the formal triple bonds required to give the chromium atoms the favored 18-electron configurations. These Cp₂Cr₂(CS)₂(CO)₂ structures are closely related to the known structure for Cp₂Cr₂(CO)₄. In addition, several doubly bridged structures with four-electron donor η²-μ-CS bridges are found for Cp₂Cr₂(CS)₂(CO)₂ at higher energies. The global minimum Cp₂Cr₂(CS)₂(CO) structure is a triply bridged triplet with a CrCr triple bond (2.299 Å by BP86). A higher energy singlet Cp₂Cr₂(CS)₂(CO) structure has a shorter Cr-Cr distance of 2.197 Å (BP86) suggesting the formal quadruple bond required to give each chromium atom the favored 18-electron configuration.     

13C NMR spectra of coordinated propargyl cations [Cp2Mo2(CO)4(μ-η2,η3-(HC≡CCR1R2)]+ BF4/?

A strong deshielding effect is observed for the carbon signal of carbocation center (C⁺) in the ¹³C NMR spectra of coordinated propargyl cations [Cp₂Mo₂(CO)₄(μ-η²,η³-(HC≡CCR¹R²)]⁺ BF₄⁻ (R¹ = R² = H) 1, (R¹ = Me, R² = H) 2, and (R¹ = R² = Me) 3 when hydrogen is replaced by methyl; the effect increases with the Mo-C⁺ distance (75.37, 98.3, and 148.68 ppm for compounds 1, 2, and 3, respectively). This indicates that the back-donation of electron density from the metal onto the ligand makes a substantial contribution to the stabilization of these cations. Original Russian Text ? I.V. Barinov, V.A. Chertkov, 2009, published in Vestnik Moskovskogo Universiteta. Khimiya, 2009, No. 1, pp. 29–34.     

1,2,3,4,7-Pentamethylindenyl complex [(η5-C9H2Me5)RhI2]2 as a synthon for the [(η5-C9H2Me5)Rh]2+ fragment

The reaction of the iodide complex [(η⁵-C₉H₂Me₅)RhI₂]₂ (1) or the acetonitrile complex [(η⁵-C₉H₂Me₅)Rh(MeCN)₃]²⁺ with Tl[Tl(η-7,8-C₂B₉H₁₁)] afforded rhodacarborane (η⁵-C₉H₂Me₅)Rh(7,8-C₂B₉H₁₁) (2). The cationic triple-decker complex with the bridging boratabenzene ligand [Cp*Fe(μ-η:η-C₅H₃Me₂BMe)Rh(η⁵-C₉H₂Me₅)]²⁺ (3) was synthesized by the reaction of the nitromethane solvate [(η⁵-C₉H₂Me₅)Rh(MeNO₂)₃]²⁺ with the sandwich compound Cp*Fe(η-C₅H₃Me₂BMe). The structure of 2 was established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1623–1625, August, 2008.     

双核Fe配合物[(η5-C5H4)C6H10(C4H3S)Fe(CO)2]2的合成和晶体结构

由侧链带有噻吩的环戊二烯基配体C5H5C6H10C4H3S与Fe(CO)5在二甲苯中加热回流,合成了1个新颖的四羰基二铁配合物[(η5-C5H4)C6H10(C4H3S)Fe(CO)2]2。通过元素分析、IR、1H NMR对其结构进行了表征,用X-射线单晶衍射确定了其结构。X-射线单晶衍射表明配合物中有2个桥羰基和2个端羰基,Fe-Fe的键长为0.25465(10)nm。     

An Electron-Deficient Triosmium Cluster Containing the Thianthrene Ligand: Synthesis, Structure and Reactivity of [Os3(CO)9(μ3-η2-C12H7S2)(μ-H)]

Reaction of [Os₃(CO)₁₀(CH₃CN)₂] with thianthrene at 80 °C leads to the nonacarbonyl dihydride compound [Os₃(CO)₉(μ-3,4-η²-C₁₂H₆S₂)(μ-H)₂] (1) and the 46-electron monohydride compound [Os₃(CO)₉(μ₃-η²-C₁₂H₇S₂)(μ-H)] (2). Compound 2 reacts reversibly with CO to give the CO adduct [Os₃(CO)₁₀(μ-η²-C₁₂H₇S₂)(μ-H)] (3) whereas with PPh₃ it gives the addition product [Os₃(CO)₉)(PPh₃)(μ-η²-C₁₂H₇S₂)(μ-H)] (4) as well as the substitution product 1,2-[Os₃(CO)₁₀((PPh₃)₂] (5) Compound 2 represents a unique example of an electron-deficient triosmium cluster in which the thianthrene ring is bound to cluster by coordination of the sulfur lone pair and a three-center-two-electron bond with the C(2) carbon which bridges the same edge of the triangle as the hydride. Electrochemical and DFT studies which elucidate the electronic properties of 2 are reported. Dedicated to the memory of a great scientist, F. Albert Cotton.