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1.
Min Wang Yang Xu Donghui Wei Prof. Rongqiang Tian Prof. Zheng Duan Prof. François Mathey 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(66):15036-15039
tert-Butylthiophosphinidene complex [tBuSP-W(CO)5] was generated by dissociation of 1-(tert-butylthio)phosphirane–W(CO)5 complex under mild conditions. The formation of transient [tBuSP-W(CO)5] was indicated by trapping reactions with 2,3-dimethyl-1,3-butadiene, alkynes, phenanthrene-9,10-dione, and methanol. The LUMO of [MeSP-W(CO)5] is significantly lower in energy than those of [Me2NP-W(CO)5], [MeOP-W(CO)5], and [Me2PP-W(CO)5]. The HOMO of [MeSP-W(CO)5] contains a significant contribution from the in-plane lone pair of P and the LUMO shows a typical π* characteristic. Since stabilized by sulfur lone pair and coordinated by W(CO)5, [tBuSP-W(CO)5] undergoes facile and reversible cycloadditions with alkenes and alkynes. 相似文献
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The reaction of the K2[Fe3Q(CO)9] clusters (Q = Se or Te) with Rh2(CO)4Cl2 under mild conditions is accompanied by complicated fragmentation of cores of the starting clusters to form large heteronuclear
cluster anions. The [PPh4][Fe4Rh3Se2(CO)16] and [PPh4]2[Fe3Rh4Te2(CO)15] compounds were isolated by treatment of the reaction products with tetraphenylphosphonium bromide. The structures of the
products were established by X-ray diffraction. In both compounds, the core of the heteronuclear cluster consists of two octahedra
fused via a common Rh3 face.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 775–778, May, 2006. 相似文献
4.
Clendenning SB Hitchcock PB Lappert MF Merle PG Nixon JF Nyulászi L 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(25):7121-7128
Treatment of the lithium amide Li[NPh(SiMe3)] with 2,4,6-tri-tert-butyl-1,3,5-triphosphabenzene, P(3)C(3)tBu(3), in a 1:2 ratio afforded equimolar amounts of the lithium salt of the five-membered 2,4,5-tri-tert-butyl-1,3-diphospholide anion, LiP(2)C(3)tBu(3) (isolated as its N,N,N',N'-tetramethylethylenediamine (TMEDA) adduct), and the tricyclic compound 6-[phenyl(trimethylsilyl)amino]-3,5,7-tri-tert-butyl-1,2,4,6-tetraphosphatricyclo[3.2.0.0(2,7)]hept-3-ene. Both compounds have been structurally characterised by single-crystal X-ray diffraction studies. The mechanism of this remarkable reaction has been elucidated by theoretical methods at the B3LYP/6-311+G** level of theory. The reaction involves a hitherto unobserved aminophosphinidene, which was formed by abstraction of a phosphorus atom from triphosphabenzene. The intermediate aminophosphinidene, which is further stabilised by the solvent THF, shows, in agreement with previous theoretical predictions, enhanced stability and reacts then with a second molecule of triphosphabenzene. 相似文献
5.
de Meijere A Khlebnikov AF Kozhushkov SI Yufit DS Chetina OV Howard JA Kurahashi T Miyazawa K Frank D Schreiner PR Rinderspacher BC Fujisawa M Yamamoto C Okamoto Y 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(22):5697-5721
(P)-(+)-Hexaspiro[2.0.0.0. 0.0.2.1.1.1.1.1]pentadecane [(P)-17] as well as (M)-(-)- and (P)-(+)-octaspiro[2.0.0.0.0.0.0.0.2.1.1.1.1.1.1.1]nonadecanes [(M)- and (P)-25]-enantiomerically pure unbranched [7]- and [9]triangulanes-have been prepared starting from racemic THP-protected (methylenecyclopropyl)methanol 6. The relative configurations of all important intermediates as well as the absolute configurations of the key intermediates were established by X-ray crystal structure analyses. This new convergent approach to enantiomerically pure linear [n]triangulanes for n=7, 9 was also tested in two variants towards [15]triangulane. Some of the most prominent and unexpected features of the newly prepared compounds are the remarkable modes of self-assembly of the diols (P)-14, (E)-(3S,3'S,4S,4'S,5R,5'R)-21, (P)-(+)-22, and (E)-31 in the solid state through frameworks of intermolecular hydrogen bonds leading to, depending on the respective structure, nanotube- [(P)-14, (P)-(+)-22, and (E)-31], honeycomb-like structures [(E)-(3S,3'S,4S,4'S,5R,5'R)-21] or a supramolecular double helix [(P)-(+)- and (M)-(-)-22]. Liquid crystalline properties of the esters and ethers of the diols (P)-14, (P)-, and (M)-22 have also been tested. Although all of these [n]triangulanes have no chromophore which would lead to significant absorptions above 200 nm, they exhibit surprisingly high specific rotations even at 589 nm with [alpha](20)(D)=+672.9 (c=0.814 in CHCl(3)) for (P)-(+)-17, +909.9 (c=0.96 in CHCl(3)) for (P)-(+)-25, -890.5 (c=1.01 in CHCl(3)) for (M)-(-)-25, and -1302.5 (c=0.36 in CHCl(3)) for (M)-(-)-39, and the specific rotations increase drastically on going to shorter wavelengths. This outstanding rotatory power is in line with their rather rigid helical arrangement of sigma bonds, and accordingly these helically shaped unbranched [n]triangulanes may be termed "sigma-[n]helicenes", as they represent the sigma-bond analogues of the aromatic pi-[n]helicenes. Density functional theory (DFT) computations at the B3 LYP/6-31+G(d,p) level of theory for the geometry optimization and time-dependent DFT for determining optical rotations with a triplet-zeta basis set (B3 LYP/TZVP) reproduce the optical rotatory dispersions (ORD) very well for the lower members (n=4, 5) of the sigma-[n]helicenes. For the higher ones (n=7, 9, 15) the computed specific rotations turn out increasingly larger than the experimental values. The remarkable increase of the specific rotation with an increasing number of three-membered rings is proportional neither to the molecular weight nor to the number of cyclopropane rings in these sigma-[n]helicenes. 相似文献
6.
Synthesis and Crystal Structure of [C(NMe2)3]2[(CO)4Fe(μ‐InCl2)2Fe(CO)4] Treatment of [C(NMe2)3]2[(CO)4FeInCl3] ( 1 ) with hot water produces the dinuclear complex [C(NMe2)3]2[(CO)4Fe(μ‐InCl2)2Fe(CO)4] ( 2 ) which could be crystallized from dichloromethane/pentane. 2 crystallizes in the monoclinic space group P21/n with a = 835.7(1), b = 1187.8(1), c = 1902.7(1) pm, β = 91.877(5)° and Z = 2. The anion contains a four‐membered Fe—In—Fe—In ring with octahedral environment at the iron atom and tetrahedral coordination at the In atom. 相似文献
7.
Hamao Watanabe Motohiko Kato Tadashi Okawa Yuichi Kougo Yoichiro Nagai Midori Goto 《应用有机金属化学》1987,1(2):157-169
The crystal structures of octaisopropylcyclotetrasilane [i-Pr2Si]4 (1) and octakis(trimethylsilylmethyl)cyclotetrasilane [(Me3SiCH2)2Si]4 (2) have been determined by means of X-ray diffraction analysis. Various crystallographic and structural data for the two compounds were recorded. The Si4 rings of the compounds are nonplanar with quite large dihedral angles of 37.1° in (1) and 36.6° in (2), being comparable to that (36.8)° for [t-BuMeSi]4 reported previously and other characteristic features in the structures of (1) and (2) were described. Some structural properties of the cyclic catenation systems, [R1R2Si]n (n = 3–6), including (1) and (2) were also discussed from a comparative viewpoint with respect to the ring shape and the relationship between ring size and Si-Si bond length. 相似文献
8.
Kiyosei Takasu Prof. Yuuki Nagamoto Yoshiji Takemoto Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(28):8427-8432
An unusual ring‐contraction rearrangement to give spirocyclopropanes from fused cyclobutanols (see scheme) has been developed. It is found that the strain energy of the substrates derived from an additional fused ring and the stereoelectronic effect of the migrating σ bond are important factors. It is noteworthy that the rearrangement proceeds in a stereospecific manner. Moreover, the method provides a spiro(cyclopropane–indane) framework from tricyclo[6.3.0.02,5]undecane, which corresponds to illudane and the protoilludane skeleton. 相似文献
9.
Alkoxo Compounds of Iron(III): Syntheses and Characterization of [Fe2(OtBu)6], [Fe2Cl2(OtBu)4], [Fe2Cl4(OtBu)2] and [N(nBu)4]2[Fe6OCl6(OMe)12] The reaction of iron(III)chloride in diethylether with sodium tert‐butylat yielded the homoleptic dimeric tert‐‐butoxide Fe2(OtBu)6 ( 1 ). The chloro‐derivatives [Fe2Cl2(OtBu)4] ( 2 ), and [Fe2Cl4(OtBu)2] ( 3 ) could be synthesized by ligand exchange between 1 and iron(III)chloride. Each of the molecules 1 , 2 , and 3 consists of two edge‐sharing tetrahedrons, with two tert‐butoxo‐groups as μ2‐bridging ligands. For the synthesis of the alkoxides 1 , 2 , and 3 diethylether plays an important role. In the first step the dietherate of iron(III)chloride FeCl3(OEt2)2 ( 4 ) is formed. The reaction of iron(III)chloride with tetrabutylammonium methoxide in methanol results in the formation of a tetrabutylammonium methoxo‐chloro‐oxo‐hexairon cluster [N(nBu)4]2[Fe6OCl6(OMe)12] ( 5 ). Crystal structure data: 1 , triclinic, P1¯, a = 9.882(2) Å, b = 10.523(2) Å, c = 15.972(3) Å, α = 73.986(4)°, β = 88.713(4)°, γ = 87.145(4)°, V = 1594.4(5) Å3, Z = 2, dc = 1.146 gcm—1, R1 = 0.044; 2 , monoclinic, P21/n, a = 11.134(2) Å, b = 10.141(2) Å, c = 12.152(2) Å und β = 114.157(3)°, V = 1251.8(4) Å3, Z = 2, dc = 1.377 gcm—1, R1 = 0.0581; 3 , monoclinic, P21/n, a = 6.527(2) Å, b = 11.744(2) Å, c = 10.623(2), β = 96.644(3)°, V = 808.8(2) Å3, Z = 2, dc = 1.641 gcm—1, R1 = 0.0174; 4 , orthorhombic, Iba2, a = 23.266(5) Å, b = 9.541(2) Å, c = 12.867(3) Å, V = 2856(2) Å3, Z = 8, dc = 1.444 gcm—1, R1 = 0.0208; 5 , trigonal, P31, a = 13.945(2) Å, c = 30.011(6) Å, V = 5054(2) Å3, Z = 6, dc = 1.401 gcm—1; Rc = 0.0494. 相似文献
10.
Sodium cyanoborohydride has been found to be very effective for the conversion of [(h5-C5H5)Fe(CO)2(h2-alkene)]+BF4? complexes to the corresponding h1-alkyl derivatives. 相似文献
11.
Vincenzo G. Albano Carlo Castellari Cristina Femoni M. Carmela Iapalucci Giuliano Longoni Magda Monari Stefano Zacchini 《Journal of Cluster Science》2001,12(1):75-87
The new Au8{Fe(CO)4}4(P^P)2 and Au6Cu2{Fe(CO)4}4(P^P)2 (P^P=dppm, dppe) neutral cluster compounds were isolated in good yields by condensation of the [Au3{Fe(CO)4}2(P^P)]- anions with Au(SEt2)Cl and CuCl, respectively, and have been characterized by IR, NMR and microanalyses. The molecular structures of Au8{Fe(CO)4}4(dppe)2 and Au6Cu2{Fe(CO)4}4(dppe)2 have been determined by X-ray diffraction studies. Both molecules adopt a stereogeometry of the heavy atoms consisting of a triangulated and corrugated ribbon twisted around the elongation direction. Contrary to the expectations the latter displays the two copper atoms in the sites of highest connectivity. This implies that site exchange between copper and gold occurs during the synthesis. 相似文献
12.
The clusters Fe2Ru(CO)12–n
(CNBu
t
)
n
(3, n=1; 4, n=2), FeRu2(CO)12–n
(CNBu
t
)
n
(5, n=1, 6, n=2) and FeRu2(CO)11(CNCy) (5a) have been prepared by direct substitution from the parent carbonyl precursors Fe2Ru(CO)12 (1) and FeRu2(CO)12 (2). All compounds have been characterized spectroscopically and clusters 3, 4, 5, and 6 by single crystal X-ray determinations. In all cases, the isonitrile ligands adopt axial or pseudo-axial positions on a ruthenium atom. The structures of 3–5 are very similar to their parent clusters, but the extent of metal framework disorder is significantly less. Cluster 6 adopts the same C
2v Fe3(CO)12 type structure as 4, and thus differs markedly from the parent compound 2, which has a D
3 structure . 相似文献
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Density functional theory (DFT) calculations on trans-dioxo metal complexes containing saturated amine ligands, trans-[M(O)2(NH3)2(NMeH2)2]2+ (M=Fe, Ru, Os), were performed with different types of density functionals (DFs): 1) pure generalized gradient approximations (pure GGAs): PW91, BP86, and OLYP; 2) meta-GGAs: VSXC and HCTH407; and 3) hybrid DFs: B3LYP and PBE1PBE. With pure GGAs and meta-GGAs, a singlet d2 ground state for trans-[Fe(O)2(NH3)2(NMeH2)2]2+ was obtained, but a quintet ground state was predicted by the hybrid DFs B3LYP and PBE1PBE. The lowest transition energies in water were calculated to be at lambda approximately 509 and 515 nm in the respective ground-state geometries from PW91 and B3LYP calculations. The nature of this transition is dependent on the DFs used: a ligand-to-metal charge-transfer (LMCT) transition with PW91, but a pi(Fe-O)-->pi*(Fe-O) transition with B3LYP, in which pi and pi* are the bonding and antibonding combinations between the dpi(Fe) and ppi(O(2-)) orbitals. The FeVI/V reduction potential of trans-[Fe(O)2(NH3)2NMeH2)2]2+ was estimated to be +1.30 V versus NHE based on PW91 results. The [Fe(qpy)(O)2](n+) (qpy=2,2':6',2':6',2':6',2'-quinquepyridine; n=1 and 2) ions, tentatively assigned to dioxo iron(V) and dioxo iron(VI), respectively, were detected in the gas phase by high-resolution ESI-MS spectroscopy. 相似文献
15.
Enantiomerically enriched bicyclo[m.1.0]alkan-2-ones having larger ring sizes between five and 16 members were prepared and subjected to additions of nucleophiles to the carbonyl carbon. Such additions were efficient and highly diastereoselective for all nucleophiles for bicycles with ring sizes greater than seven. Diastereoselectivity for these additions is rationalized by assuming early transition states and exposure of the same carbonyl face to the ring exterior in the vast majority of populated conformers for each bicyclic ketone. 相似文献
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Anna Vizi-Orosz 《Journal of organometallic chemistry》1976,111(1):61-64
The Pn[Co(CO)3]4?n (n = 1, 2, 3) tetrahedral clusters have been prepared and characterized. The very unstable PCo3(CO)9 can be stabilized in the form of (CO)4FePCo3(CO)9 相似文献
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Binbin Zhou Dr. Jose M. Goicoechea 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(36):11145-11150
Reaction of cyclooctatetraene (COT) iron(II) tricarbonyl, [Fe(cot)(CO)3], with one equivalent of K4Ge9 in ethylenediamine (en) yielded the cluster anion [Ge8Fe(CO)3]3? which was crystallographically‐characterized as a [K(2,2,2‐crypt)]+ salt in [K(2,2,2‐crypt)]3[Ge8Fe(CO)3]. The chemically‐reduced organometallic species [Fe(η3‐C8H8)(CO)3]? was also isolated as a side‐product from this reaction as [K(2,2,2‐crypt)][Fe(η3‐C8H8)(CO)3]. Both species were further characterized by EPR and IR spectroscopy and electrospray mass spectrometry. The [Ge8Fe(CO)3]3? cluster anion represents an unprecedented functionalized germanium Zintl anion in which the nine‐atom precursor cluster has lost a vertex, which has been replaced by a transition‐metal moiety. 相似文献