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1.
Hans Georg von Schnering Prof. Dr. Dr. h. c. Jen-Hui Chang Maria Freiberg Karl Peters Eva-Maria Peters Alim Ormeci Liane Schröder Gerhard Thiele Prof. Dr. Caroline Röhr 《无机化学与普通化学杂志》2004,630(1):109-116
The isotypical crystal structures of the mixed valent trihalides PtCl3 and PtBr3 were redetermined by single crystal methods (space group R3¯; trigonal setting; PtCl3: a = 21.213Å, c = 8.600Å, c/a = 0.4054; Z = 36; 1719 hkl; R = 0.035; PtBr3: a = 22.318Å, c = 9.034Å; c/a = 0.4048; Z = 36; 1606 hkl; R = 0.027). A cubic closest packing of X— anions forms the basis of an optimized arrangement of cuboctahedrally [Pt6X12] cluster molecules with PtII and enantiomers of helical chains of edge‐condensed [PtX2X4/2] octahedra with PtIV in cis‐Δ‐ and cis‐Λ‐configuration, respectively. The bond lengths vary with the function of the X— ligands (d¯(PtII—X) = 2.315 and 2.445Å; d¯(PtII—PtII) = 3.336 and 3.492Å; d(PtIV—X) = 2.286 — 2.417Å and 2.437 — 2.563Å). The PtII atoms are shifted outwards the X12 cuboctahedra by 0.045Å and 0.024Å, respectively. The symmetry governed Periodic Nodal Surface, PNS, perfectly separates the regions of different valencies. Quantum chemical calculations exclude the possible additional interactions between PtII and one of the exo‐ligands of PtIV. 相似文献
2.
The γ‐brass type phase Pt2Zn11—δ (0.2 < δ < 0.3) was prepared by reaction of the elements in evacuated silica ampoules. The structures of crystals grown in the presence of excess zinc or alternatively excess platinum were determined from single crystal X‐ray diffraction intensities and confirmed by Rietveld profile fits. Pt2Zn10.72(1) crystallizes in the space group I4¯3m, a = 908.55(4) pm, Z = 4. The structure refinement converged at RF = 0.0302 for Io > 2σ (Io) for 293 symmetrically independent intensi ties and 19 variables. The structure consists of a 26 atom cluster which is comprised of four crystallographically distinct atoms. The atoms Zn(1), Pt(1), Zn(2) and Zn(3) form an inner tetrahedron IT, an outer tetrahedron OT, an octahedron OH, and a distorted cuboctahedron CO respectively. About 14 % of the Zn(1) sites are unoccupied. Pt2Zn10.73 melts at 1136(2) K. It is a moderate metallic conductor (ρ298 = 0.2—0.9 mΩ cm) whose magnetic properties (χmol = —4.6 10—10 to —5.4 10—10 m3 mol—1) are dominated by the core diamagnetism of its components. 相似文献
3.
Dirk Steinborn Tobias Hoffmann Michael Gerisch Clemens Bruhn Harry Schmidt Karsten Nordhoff Julian A. Davies Kristin Kirschbaum Ingo Jolk 《无机化学与普通化学杂志》2000,626(3):661-666
The platina‐β‐diketones [Pt2{(COR)2H}2(μ‐Cl)2] ( 1 , R = Me a , Et b ) react with phosphines L in a molar ratio of 1 : 4 through cleavage of acetaldehyde to give acylplatinum(II) complexes trans‐[Pt(COR)Cl(L)2] ( 2 ) (R/L = Me/P(p‐FC6H4)3 a , Me/P(p‐CH2=CHC6H4)Ph2 b , Me/P(n‐Bu)3 c , Et/P(p‐MeOC6H4)3 d ). 1 a reacts with Ph2As(CH2)2PPh2 (dadpe) in a molar ratio of 1 : 2 through cleavage of acetaldehyde yielding [Pt(COMe)Cl(dadpe)] ( 3 a ) (configuration index: SP‐4‐4) and [Pt(COMe)Cl(dadpe)] (configuration index: SP‐4‐2) ( 3 b ) in a ratio of about 9 : 1. All acyl complexes were characterized by 1H, 13C and 31P NMR spectroscopy. The molecular structures of 2 a and 3 a were determined by single‐crystal X‐ray diffraction. The geometries at the platinum centers are close to square planar. In both complexes the plane of the acyl ligand is nearly perpendicular to the plane of the complex (88(2)° 2 a , 81.2(5)° 3 a ). 相似文献
4.
Synthesis of β‐Haloketones by β‐Addition Reactions of α,β‐Unsaturated Ketones with BX3 (X = Br,Cl) as Halide Source
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A series of β‐bromoketones and β‐chloroketones were synthesized by the addition reactions of α,β‐unsaturated ketones under BX3 (X = Br, Cl) and ethylene glycol reaction system. The α,β‐unsaturated ester also was successfully converted to its corresponding β‐bromoester under the reaction condition. 相似文献
5.
Natalya V. Kirij Wieland Tyrra Dieter Naumann Ingo Pantenburg Yurii L. Yagupolskii 《无机化学与普通化学杂志》2006,632(2):284-288
Ligand exchange reactions of cis‐PtCl2(PPh3)2 and [NMe4]SCF3 in different ratios were studied. Depending on the stoichiometry reactions proceeded with formation of products expected for the chosen ratio, i. e. cis‐Pt(SCF3)Cl(PPh3)2, cis‐Pt(SCF3)2(PPh3)2, and [NMe4][Pt(SCF3)3(PPh3)]. Starting from cis‐PtCl2(MeCN)2 and [NMe4]SCF3 and adding PPh3 after substitution, product mixtures were dominated by the corresponding trans‐isomers. Results of the single crystal structure analyses of cis‐Pt(SCF3)2(PPh3)2 and trans‐Pt(SCF3)Cl(PPh3)2 are discussed. 相似文献
6.
Jos S. Casas Alfonso Castieiras Emilia García‐Martínez Yolanda Paraj M. Luz Prez‐Parall Angeles Snchez‐Gonzlez Jos Sordo 《无机化学与普通化学杂志》2005,631(11):2258-2264
Compounds of type [MX2(Hpben)] [M = Pd (X = Cl), Pt (X = Cl, I); Hpben = 2‐(2′‐pyridyl)benzimidazole] were prepared and characterized, and the structures of the Pt derivatives were determined by X‐ray crystallography. The crystals of [PtI2(Hpben)] consist of discrete units in which the Pt atom is coordinated to two iodine atoms and to pyridine and imidazole N atoms in a distorted square planar arrangement. The structure of the chloro derivative is similar, except that the [PtCl2(Hpben)] monomers are hydrogen‐bonded in zig‐zag chains. In assays of the interactions of the Pd and Pt chloro compounds with DNA, and of their in vitro cytotoxic activity against human cervical carcinoma cells (HeLa‐229), human ovarian carcinoma cells (A2780) and a cisplatin‐resistant mutant A2780 line (A2780cis), the only activity observed was modest cytotoxicity of the Pd derivative for A2780. 相似文献
7.
The η2‐thio‐indium complexes [In(η2‐thio)3] (thio = S2CNC5H10, 2 ; SNC4H4, (pyridine‐2‐thionate, pyS, 3 ) and [In(η2‐pyS)2(η2‐acac)], 4 , (acac: acetylacetonate) are prepared by reacting the tris(η2‐acac)indium complex [In(η2‐acac)3], 1 with HS2CNC5H10, pySH, and pySH with ratios of 1:3, 1:3, and 1:2 in dichloromethane at room temperature, respectively. All of these complexes are identified by spectroscopic methods and complexes 2 and 3 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 : space group, C2/c with a = 13.5489(8) Å, b = 12.1821(7) Å, c = 16.0893(10) Å, β = 101.654(1)°, V = 2600.9(3) Å3, and Z = 4. The structure was refined to R = 0.033 and Rw = 0.086; Crystal data for 3 : space group, P21 with a = 8.8064 (6) Å, b = 11.7047 (8) Å, c = 9.4046 (7) Å, β = 114.78 (1)°, V = 880.13(11) Å3, and Z = 2. The structure was refined to R = 0.030 and Rw = 0.061. The geometry around the metal atom of the two complexes is a trigonal prismatic coordination. The piperidinyldithiocarbamate and pyridine‐2‐thionate ligands, respectively, coordinate to the indium metal center through the two sulfur atoms and one sulfur and one nitrogen atoms, respectively. The short C‐N bond length in the range of 1.322(4)–1.381(6) Å in 2 and C‐S bond length in the range of 1.715(2)–1.753(6) Å in 2 and 3 , respectively, indicate considerable partial double bond character. 相似文献
8.
The reaction of platinum(II) chloride with 1,2,4‐trichlorobenzene gives the novel platinum complex Pt6Cl12·(1,2,4‐C6H3Cl3). It is the first example of an cocrystallization product of platinum(II) chloride and organic molecules whose crystal structure has been established. 相似文献
9.
The Reactivity of Dinuclear Platina‐β‐diketones with Phosphines: Diacetylplatinum(II) Complexes and Mononuclear Platina‐β‐diketones Addition of mono‐ and bidentate phosphines or of AsPh3 to the platina‐β‐diketone [Pt2{(COMe)2H}2(μ‐Cl)2] ( 1 ) followed by the addition of NaOMe at ?70 °C resulted in the formation of diacetyl platinum(II) complexes cis‐[Pt(COMe)2L2] (L = PPh3, 2a ; P(4‐FC6H4)3, 2b ; PPh2(4‐py), 2c ; PMePh2, 2d ; AsPh3, 2d ) and [Pt(COMe)2(L??L)] (L??L = dppe, 3b ; dppp, 3c ), respectively. The analogous reaction with dppm afforded the dinuclear complex cis‐[{Pt(COMe)2}2(μ‐dppm)2] ( 4 ) that reacted in boiling acetone yielding [Pt(COMe)2(dppm)] ( 3a ). The reactions 1 → 2 / 3 were found to proceed via thermally highly unstable cationic mononuclear platina‐β‐diketone intermediates [Pt{(COMe)2H}L2]+ and [Pt{(COMe)2H}(L??L)]+, respectively, that could be isolated as chlorides for L??L = dppe ( 5a ) and dppp ( 5b ). The reversibility of the deprotonation of type 5 complexes with NaOMe yielding type 3 complexes was shown by the protonation of the diacetyl complex 3b with HBF4 yielding the platina‐β‐diketone [Pt{(COMe)2H}(dppe)](BF4) ( 5c ). All compounds were fully characterized by means of NMR and IR spectroscopies, and microanalyses. X‐ray diffraction analysis was performed for the complex cis‐[Pt(COMe)2(PPh3)2]·H2O·CHCl3 ( 2a ·H2O·CHCl3). 相似文献
10.
The new complex, cis‐β‐[Cr(2,2,3‐tet)(N3)2]Br (2,2,3‐tet = 1,4,7,11‐tetraazaundecane), was prepared and its structure was determined by single‐crystal X‐ray diffraction. The chromium(III) atom is in a distorted octahedral environment coordinated by four nitrogen atoms of 2,2,3‐tet and two azido ligands in a cis‐β arrangement, with bent Cr–N3 linkages at the coordinating azide nitrogen atoms. The mean Cr–N(2,2,3‐tet) and Cr–N(azide) bond lengths are 2.084(5) and 2.021(5) Å, respectively. The crystal structure is stabilized by ionic interactions, supported by N–H ··· N(azide) and N–H ··· Br hydrogen bonds. The IR and electronic spectroscopic properties are also discussed. 相似文献
11.
The mass spectra of a series of N‐aryl α,β‐unsaturated γ‐lactams were studied. Besides the molecular ion, the three characteristic fragments such as [M+‐29], [M+‐55], and [M+‐82] were commonly found in a series of N‐Aryl α,β‐unsaturated γ‐lactams in EI/MS. Further more the mechanism for the interpretation of these fragments is also de scribed. 相似文献
12.
Ytterbium complexes supported by a linked bis(β‐ketoiminato) ligand, N,N′‐ethylenebis(benzoylacetoimine) (H2L), were synthesized and their catalytic behavior was explored. The reaction of YbCl3 with 1 equiv. of LLi2 afforded the mononuclear ytterbium chloride LYbCl(THF)2 ( 1 ) in high yield. Complex 1 can be used as starting material to prepare β‐ketoiminate‐ytterbium derivatives. Treatment of complex 1 with NaN(SiMe3)2 produced the dimeric ytterbium amide {LYb[N(SiMe3)2]}2 ( 2 ), while the similar reaction of complex 1 with NaOAr (ArO = 2, 6‐tBu‐4‐MeC6H2O) led to the mononuclear ytterbium aryloxide LYbOAr(THF) ( 3 ). The three complexes were well detected by elemental analysis and single‐crystal X‐ray analysis. It was found that complexes 2 and 3 can initiate the ring‐opening polymerization of ?‐caprolactone with moderate activity. 相似文献
13.
A series of β,γ‐unsaturated ketones were isomerized to their corresponding α,β‐unsaturated ketones by the introduction of DABCO in iPrOH at room temperature. The endo‐cyclic double bond (β,γ‐position) on ketone was rearranged to exo‐cyclic double bond (α,β‐position) under the reaction conditions. 相似文献
14.
Synthesis and X‐ray Crystal Structures of Zinc Dichloride Complexes Supported by a β‐Diimine Ligand
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Christoph Scheiper Dominik Naglav Dieter Bläser Christoph Wölper Stephan Schulz 《无机化学与普通化学杂志》2015,641(5):871-875
β‐Diimine zinc dichloride complexes [CH2{C(Me)NAr}2]ZnCl2 [Ar = Mes ( 1 ), Dipp ( 2 )] were obtained from the reactions of ZnCl2 with the corresponding β‐iminoamines [ArN(H)C(Me)CHC(Me)NAr]. Complexes 1 and 2 were characterized by multinuclear NMR (1H, 13C) and IR spectroscopy, elemental analyses as well as by single‐crystal X‐ray diffraction. The energy differences between the enamine‐imine tautomers of the β‐iminoamines were quantified by quantum chemical calculations. 相似文献
15.
Rosa Carballo Berta Covelo Ezequiel M. Vzquez‐Lpez Emilia García‐Martínez Alfonso Castieiras 《无机化学与普通化学杂志》2002,628(5):907-908
The compound [Cu4(μ2‐OH)2(μ3‐OH)2Cl2(bipy)4]Cl2 · 6H2O ( 1 ) was obtained by recrystallization of [Cu(HB)2(2, 2′‐bipy)] · H2O (H2B = diphenylglycolic acid) from EtOH/CH2Cl2 and their structure has been determined by single‐crystal X‐ray analysis. The cationic complex may be described as based on a Cu4(OH)4 core with a “stepped cubane” structure. The coordination polyhedron around each copper is a distorted square pyramid. The tetranuclear units are linked in the crystal by C‐H…Cl hydrogen bonds and by π‐π interactions between bipyridine rings. IR data are also presented. 相似文献
16.
A series of N‐aryl 2‐alkenamides were produced efficiently by treating N‐aryl 3‐(phenylsulfonyl)‐propanamides with potassium tert‐butoxide in THF at 0°C. With out isolation, it was further treated with an additional equivalent of potassium tert‐butoxide and allyl bromide to give N‐allyl N‐aryl 2‐alkenamides in one pot in good yields. Followed by a ring‐closing metathesis reaction, these N‐allyl N‐aryl 2‐alkenamides were respectively converted into corresponding N‐aryl α,β‐unsaturated γ‐lactams in moderate yields. 相似文献
17.
Reaction of Ndcl3 with AlCl3 and mesitylene in benzene gives complex [Nd(η6‐1, 3, 5‐C6H3Me3)‐(AlCl4)3](C6H6) (1) which was characterized by elemental analysis, IR spectra, MS and X‐ray diffractions. The X‐ray determination indicates that 1 has a distorted pentagonal bipyramidal geometry and crystallizes in the monoclinic, space group P21/n with a = 0.9586(2), b = 1.1717(5), c = 2.8966(7) nm, β = 90.85 (2)°, V = 3.2529 (6) nm3,Dc= 1.573 g/cm3, Z = 4. A comparison of bond parameters for all the reported Ln (η6‐Ar) (AlCl4)3 complexes indicates that the bond distance of La? C is shortened with the increasing of methyl group on benzene and with the decreasing of radius of lanthanide ions. 相似文献
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20.
Synthesis of new optically active α,α′,β‐trisubstituted‐β‐lactones as monomers for stereoregular biopolyesters
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Rima Belibel Christel Barbaud 《Journal of polymer science. Part A, Polymer chemistry》2015,53(22):2586-2597
Various optically active (4R)‐alkyloxycarbonyl‐3,3‐dialkyl‐2‐oxetanones as monomers were synthesized from L‐(S)‐malic acid in six steps to prepare a new family of stereopolyesters for biomedical applications. The synthesis began with an esterification followed of a dialkylation in the aim to introduce hydrophobic groups as methyl or reactive group as allyl. Then, a saponification has permitted to obtain the corresponding diacids that reacted with appropriate alcohols to furnish different monoesters. The last and most important step was activation of hydroxyl group of monoesters with the asymmetric carbon configuration inversion according to the Mitsunobu reaction. Thus, this reaction has provided lactones from monoesters with 100% enantiomeric excess which was confirmed by 1H NMR and by the synthesis of corresponding isotactic and semicrystalline homopolyesters. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2586–2597 相似文献