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1.
<正> The crystal and molecular structures of (μ-PhCH2S)(μ-CH3C(O)CH2S)-Fe2(CO)6 have been determined by X-ray diffraction technique. The complex has chemical formula of C16H12O7S2Fe2 and Mr=492.08. The crystals are tri-clinic, space group P1,with a=8.461(5), b=10.937(5), c=ll.419(4)A,α=81.61 (3), β=78.21(4),γ=71.04(4)°,V=974.5A3, Dc=1.68 gcm-3,μ(MoKα)=17.3cm-1, Z=2,F(000)=495.93. The final R was 0.038 for 2874 independent reflections.  相似文献   

2.
(R)-Phenylglycinol is shown to be an efficient building block for the synthesis of chiral amino diols in pure diastereomeric form by epoxide ring-opening reactions. The reaction with rac-trans-stilbene oxide gives [HOCH(2)-(R)-PhCH]NH[(S)-PhCH-(R)-PhCHOH] [2(R)-3(R)-4(S)-HNO(2)H(2)] in 32% yield, which can be methylated at nitrogen to give enantiomerically pure [HOCH(2)-(R)-PhCH]NCH(3)[(S)-PhCH-(R)-PhCHOH] [2(R)-3(R)-4(S)-MeNO(2)H(2)]. These amino diol ligands have been used to prepare chiral dioxomolybdenyl complexes of the formula N(R)-2(R)-3(R)-4(S)-(HNO(2))MoO(2) (1) and N(R)-2(R)-3(R)-4(S)-(MeNO(2))MoO(2) (2). The absolute configuration at each stereocenter in the Mo(VI) complexes has been established by (1)H NOESY spectroscopy. The configuration determined for 1 has been confirmed by an X-ray analysis. Crystal data: orthorhombic P2(1)2(1)2(1), a =7.620(3), b = 13.589(2), c = 20.339(3) ?, Z = 4, R = 0.0336. The structure consists of a polymeric chain of N(R)-2(R)-3(R)-4(S)-(HNO(2))MoO(2) molecules connected through unsymmetrical Mo=O --> Mo bridges. Each metal center is coordinated in a distorted octahedral geometry by a cis dioxo unit and by two trans alkoxo atoms. The coordination polyhedron is completed by a nitrogen atom and by a bridging oxo oxygen atom from an adjacent molecule. Compound 2 catalyzes the oxidation of PPh(3) to OPPh(3) by DMSO through a mechanism that involves the intermediacy of a Mo(IV) species.  相似文献   

3.
New hydrazone o-HO-phenylhydrazo-β-diketones (OHADB), R(1)NHN═CR(2)R(3) [R(1) = HO-2-C(6)H(4), R(2) = R(3) = COMe (H(2)L(1), 1), R(2)R(3) = COCH(2)C(Me)(2)CH(2)CO (H(2)L(2), 2), R(2) = COMe, R(3) = COOEt (H(2)L(4), 4); R(1) = HO-2-O(2)N-4-C(6)H(3), R(2)R(3) = COCH(2)C(Me)(2)CH(2)CO (H(2)L(3), 3), R(2) = COMe, R(3) = COOEt (H(2)L(5), 5), R(2)R(3) = COMe (H(2)L(6), 6A)], and their Cu(II) complexes [Cu(2)(CH(3)OH)(2)(μ-L(1))(2)] 7, [Cu(2)(H(2)O)(2)(μ-L(2))(2)] 8, [Cu(H(2)O)(L(3))] 9, [Cu(2)(μ-L(4))(2)](n) 10, [Cu(H(2)O)(L(5))] 11, [Cu(2)(H(2)O)(2)(μ-L(6))(2)] 12A and [Cu(H(2)O)(2)(L(6))] 12B were synthesized and fully characterized, namely, by X-ray analysis (4, 5, 7-12B). Reaction of 6A, Cu(NO(3))(2) and ethylenediamine (en) leads, via Schiff-base condensation, to [Cu{H(2)NCH(2)CH(2)N═C(Me)C(COMe)═NNC(6)H(3)-2-O-4-NO(2)}] (13), and reactions of 12A and 12B with en give the Schiff-base polymer [Cu{H(2)NCH(2)CH(2)N═C(Me)C(COMe)═NNC(6)H(3)-2-O-4-NO(2)}](n) 14. The dependence of the OHADB tautomeric equilibria on temperature, electronic properties of functional groups, and solvent polarity was studied. The OHADB from unsymmetrical β-diketones exist in solution as a mixture of enol-azo and hydrazo tautomeric forms, while in the solid state all the free and coordinated OHADB crystallize in the hydrazo form. The relative stabilities of various tautomers were studied by density functional theory (DFT). 7-14 show catalytic activities for peroxidative oxidation (in MeCN/H(2)O) of cyclohexane to cyclohexanol and cyclohexanone, for selective aerobic oxidation of benzyl alcohols to benzaldehydes in aq. solution, mediated by TEMPO radical, under mild conditions and for the MW-assisted solvent-free synthesis of ketones from secondary alcohols with tert-butylhydroperoxide as oxidant.  相似文献   

4.
An Ir-catalyzed allylic vinylation reaction of allyl carbonates with o-aminostyrene derivatives has been realized, providing skipped (Z,E)-diene derivatives. With (E)-but-2-ene-1,4-diyl dimethyl dicarbonate as the substrate, an efficient enantioselective synthesis of 1-benzazepine derivatives via an Ir-catalyzed domino allylic vinylation/intramolecular allylic amination reaction has been developed. Mechanistic studies of the allylic vinylation reaction have been carried out, and the results suggest that the leaving group of the allylic precursor plays a key role in directing the reaction pathway. Screening of various allylic precursors showed that Ir-catalyzed reactions of allyl diethyl phosphates with o-aminostyrene derivatives proceed via an allylic amination pathway. A subsequent ring-closing metathesis (RCM) reaction of the amination products led to a series of enantiomerically enriched 1,2-dihydroquinoline derivatives. Their utility is indicated by an asymmetric total synthesis of (-)-angustureine.  相似文献   

5.
Hypophosphorous compounds (MOP(O)H(2), M = H, R(3)NH) effectively participate in metal-catalyzed C-P bond-forming reactions with allenes, dienes, and activated allylic electrophiles under mild conditions. The catalytic system Pd(2)dba(3)/xantphos is crucial to avoid or minimize the competitive reductive transfer-hydrogenation pathway available to hypophosphorous acid derivatives. Further investigation into the allylation mechanism provided access to the analogy allylic acetate-allylic phosphinate, which then led to the development of a Pd-catalyzed rearrangement of preformed allylic phosphinates esters and, ultimately, to a catalytic dehydrative allylation of hypophosphorous acid with allylic alcohols. The reactions disclosed herein constitute efficient synthetic approaches, not only to prepare allylic H-phosphinic acids but also their esters via one-pot tandem processes. In addition, the potential of H-phosphinates as useful synthons for the preparation of other organophosphorus compounds is demonstrated.  相似文献   

6.
A strictly heterodinuclear Cu-Tb complex [LCu(O(2)COMe)Tb(thd)(2)] made with a Schiff base L, thd, and monomethylcarbonate ligands [L(2-) = N,N'-2,2-dimethylpropylenedi(3-methoxysalicylideneiminato); thd = tetramethylheptanedionato] behaves like a single-molecule magnet. The monomethylcarbonate ligand, which appears during the reaction pathway, bridges the Cu and Tb ions.  相似文献   

7.
<正> [{(μ-PhCH2S)Fe2(CO)6}2(u4-S)], Mr = 837.95, triclinic, Pl,a=13.701(3),b=16.542(5), c=17.030(5)A,α=107.69(2),β=90.15(2),γ= 114.49(2)°,V=3309.3A3, Z=4, Dx=1.68 g/cm3,MoKa,λ=0.71069A μ=20.2 cm-1,F(000)=2008, room temperature, final R=0.035 for 4960 independent reflections. The molecule possesses approximate C2 symmetry with the pseudo-twofold axis passing through the unique sulfur atom u4-S(2) and the midpoint of the other two u2-sulfur atoms S(1) and S(3). The unique u4-sulfur atom has a tetrahedral geometry and donates its six valence electrons to the four iron atoms. The average Fe-(μ4-S) distance of 2.247 A is slightly shorter than the average Fe-(μ2-S) distance of 2.265A.  相似文献   

8.
To clarify the nature of five-center, six-electron (5c-6e) C(2)Z(2)O interactions, atoms-in-molecules (AIM) analysis has been applied to an anthraquinone, 1,8-(MeZ)(2)ATQ (1 (Z=Se), 2 (Z=S), and 3 (Z=O)), and a 9-methoxyanthracene system, 9-MeO-1,8-(MeZ)(2)ATC (4 (Z=Se), 5 (Z=S), and 6 (Z=O)), as well as 1-(MeZ)ATQ (7 (Z=Se), 8 (Z=S), and 9 (Z=O)) and 9-MeO-1-(MeZ)ATC (10 (Z=Se), 11 (Z=S), and 12 (Z=O)). The total electronic energy density (H(b)(r(c))) at the bond critical points (BCPs), an appropriate index for weak interactions, has been examined for 5c-6e C(2)Z(2)O and 3c-4e CZO interactions of the n(p)(O)sigma*(Z--C) type in 1-12. Some hydrogen-bonded adducts were also re-examined for convenience of comparison. The total electronic energy densities varied in the following order: OO (3: H(b)(r(c))=0.0028 au)=OO (6: 0.0028 au)>OO (9: 0.0025 au)> or =NNHF (0.0024 au)> or =OO (12: 0.0023 au)>H(2)OHOH (0.0015 au)>SO (8: 0.0013 au)=SO (2: 0.0013 au)> or =SO (11: 0.0012 au)=SO (5: 0.0012 au)>HFHF (0.0008 au)=SeO (10: 0.0008 au)=SeO (4: 0.0008 au)> or =SeO (1: 0.0007 au)> or =SeO (7: 0.0006 au)>HCNHF (-0.0013 au). H(b)(r(c)) values for SO were predicted to be smaller than the hydrogen bond of H(2)OHOH and H(b)(r(c)) values for SeO are very close to or slightly smaller than that for HFHF in both the ATQ and 9-MeOATC systems. In the case of Z=Se and S, H(b)(r(c)) values for 5c-6e C(2)Z(2)O interactions are essentially equal to those for 3c-4e CZO if Z is the same. The results demonstrate that two n(p)(O)sigma*(Z--C) 3c-4e interactions effectively connect through the central n(p)(O) orbital to form the extended hypervalent 5c-6e system of the sigma*(C--Z)n(p)(O)sigma*(Z--C) type for Z=Se and S in both systems. Natural bond orbital (NBO) analysis revealed that n(s)(O) also contributes to some extent. The electron charge densities at the BCPs, NBO analysis, and the total energies calculated for 1-12, together with the structural changes in the PhSe derivatives, support the above discussion.  相似文献   

9.
The weak-link approach has been employed to synthesize a series of bimetallic Cu(I) macrocycles in high yield. Addition of phosphinoalkylether or -thioether ligands to [Cu(MeCN)4]PF6 produces "condensed" intermediates, [mu-(1,4-(PPh2CH2CH2X)2Y)2Cu2][PF6]2 (X = S, O; Y = C6H4, C6F4), containing strong P-Cu bonds and weaker O-Cu or S-Cu bonds. The weak bonds of these intermediates can be cleaved through ligand substitution reactions to generate macrocyclic structures, [mu-(1,4-(PPh2CH2CH2X)2Y)2(Z)nCu2][PF6]2 (X = S, O; Y = C6H4, C6F4; Z = pyridine, acetonitrile, diimines, isocyanide) in nearly quantitative yields. The incorporation of tetrahedral Cu(I) metal centers into these macrocycles provides a pathway to complexes that differ from analogous d8 square planar macrocycles generated via this approach in their increased air stability, small molecule reactivity, and ability to form multiple structural isomers. Solid-state structures, as determined by single-crystal X-ray diffraction studies, are presented for condensed intermediates and an open macrocycle  相似文献   

10.
A broadly useful catalytic enantioselective synthesis of branched allylic esters from prochiral (Z)-2-alkene-1-ols has been developed. The starting allylic alcohol is converted to its trichloroacetimidate intermediate by reaction with trichloroacetonitrile, either in situ or in a separate step, and this intermediate undergoes clean enantioselective S(N)2' substitution with a variety of carboxylic acids in the presence of the palladium(II) catalyst (R(p),S)-di-μ-acetatobis[(η(5)-2-(2'-(4'-methylethyl)oxazolinyl)cyclopentadienyl-1-C,3'-N)(η(4)-tetraphenylcyclobutadiene)cobalt]dipalladium, (R(p),S)-[COP-OAc](2), or its enantiomer. The scope and limitations of this useful catalytic asymmetric allylic esterification are defined.  相似文献   

11.
本工作试图把碳钯化反应发展到双主主烯丙基体系,以考察通过杂原子导向的远端区域专一性的反应以及缩硫酮官能团对硫钯化反应的导向作用.  相似文献   

12.
Activated allylic compounds of the type RCH:CHCH(2)Z (Z = CN, CO(2)Me) react efficiently with aromatic aldehydes in the presence of 20-40 mol % of P(R'NCH(2)CH(2))(3)N at -94 to -63 degrees C. Both R = H and R = Me lead exclusively to alpha-addition products. When R = H and Z = CN, an allylic transposition occurs to afford a Baylis-Hillman product as the only product.  相似文献   

13.
The title compound, spiro[1-bromo(S)-4-(R)-hydroxy-5-oxa-6-oxo-bicyclo[3.1.0]-hxane-2,2'-(3'-diethyl-α-(S)-4'-Cl-benzyloxyphosphonyl-4'-(1R,2S,5R)-menthyloxybutyrolactone)] has been synthesized via the tandem asymmetric reaction and it crystallizes in a monoclinic system, space group P21 with a = 11.067(3), b = 12.484(2), c = 12.356(2)(A), β = 101.95°,C29H39BrC1O10P, Mr = 693.93, V= 1670.2(6) (A)3, Z= 2, Dc= 1.380 g/cm3, λ(MoKα) = 0.071073nm, μ = 1.410 mm-1, F(000) = 720, the final R = 0.0570 and wR = 0.0758 for 6190 observed reflections with I > 2σ(I). The structure is characterized by the special combination of biologic phosphonyl group and one cyclopropane as well as two butyrolactones. The intermolecular hydrogen bond between O(3)-H(3A)…O(10) in the crystal lattice has been observed.  相似文献   

14.
Pyridine-2,6-dicarboxylic acid (pdcH(2) ) reacts with nitrate salts of La(III), Ce(III), and Nd(III) under hydrothermal conditions to form three-dimensional network structures, 1-4. All the compounds crystallize in the monoclinic space group P2(1)/c with the following lattice parameters: [La(2)(pdc)(3).3H(2)O] 1, a = 10.966(3) A, b = 17.534(4) A, c = 13.578(2) A, beta = 100.23(3) degrees, V( )()= 2569.3(9) A(3), Z = 4, R1 = 0.052, wR2 = 0.143, S = 1.06; [Ce(2)(pdc)(3).3H(2)O] 2, a = 12.701(3) A, b = 9.979(1) A, c = 19.401(4) A, beta = 97.73(2) degrees, V( )()= 2436.6(8) A(3), Z = 4, R1 = 0.039, wR2 = 0.117, S = 1.30; [Ce(2)(pdc)(3).3H(2)O] 3, a = 10.961(5) A, b = 17.523(5) A, c = 13.505(2) A, beta = 100.89(3) degrees, V( )()= 2547.2(8) A(3), Z = 4, R1 = 0.040, wR2 = 0.103, S = 1.08; [Nd(2)(pdc)(3).3H(2)O] 4, a = 10.944(3) A, b = 17.448(5) A, c = 13.397(2) A, beta = 101.19(3) degrees, V( )()= 2569.3(9) A(3), Z = 4, R1 = 0.052, wR2 = 0.143, S = 1.06. Compounds 1, 3, and 4 form infinite single helical chains with large widths and pitches containing four metal ions per turn while 2 forms a different helix with smaller width and pitch containing two metal ions per turn. Each helix is further bonded on either side via carboxylate bridging producing three-dimensional metal-organic framework structures.  相似文献   

15.
[Bu~4N]~3[Mo~2FeS~8O].(CH~2OH)~2簇合物的合成, 结构和性质研究   总被引:1,自引:0,他引:1  
(NH4)2MoS~4、FeCl~3与乙二醇钠在乙二醇溶液中反应, 再与Bu~4NBr作用可得到一种M0-Fe-S簇合物[Bu~4N]~3[Mo~2FeS~8O].HOCH~2OH。其结构经X光晶体结构分析确定。并测定其红外光谱、紫外光谱、Mossbauer谱和电化学性质。该化合物可催化KBH~4转化乙炔还原为乙烯的反应。  相似文献   

16.
The title complex, (1S)-1,1'-bis{[N-ethyl-N-(1-methylethyl)-amino]carbonyl}-2- (hydroxyldiphenylmethyl)-ferrocene ([Fe(C24H22NO2)(C11H16NO)]2·H2O, Mr = 1207.13), was synthesized via (-)-Sparteine-mediated enantioselective directed ortho-lithiation of 1,1'-bis{[N- ethyl-N-(1-methylethyl)-amino]carbonyl}-2-(hydroxydiphenylmethyl)-ferrocene. The structure of the title compound was determined by X-ray single-crystal diffraction. The crystal belongs to the orthorhombic system, space group P212121, with a = 10.26...  相似文献   

17.
A highly efficient and selective synthesis of (1E)- or (1Z)-1,2-dihalo-1,4-dienes via Pd-catalyzed coupling of haloalkynes and allylic halides is described. The (1E)-1,2-dihalo-1,4-dienes were generated in good yields with excellent stereoselectivities (1E/1Z up to >98/2), while (1Z)-1,2-dihalo-1,4-dienes were produced in excellent yields and stereoselectivities (1Z/1E up to >98/2) by simply adding stoichiometric lithium halides.  相似文献   

18.
The reaction of Au(OH)(3) and oleum (65% SO(3)) in the presence of M(2)SO(4) (M = Li, Na) afforded yellow single crystals of Li[Au(S(2)O(7))(2)] (triclinic, P ?1, Z = 1, a = 532.20(3), b = 649.69(4), c = 836.72(5) pm, α = 107.982(2)°, β = 90.171(2)°, γ = 102.583(2)°, V = 267.80(3) ?(3)) and Na[Au(S(2)O(7))(2)] (monoclinic, P2(1)/n, Z = 2, a = 533.31(3), b = 1193.38(7), c = 907.67(5) pm, β = 98.548(3)°, V = 571.26(6) ?(3)). Both compounds exhibit the unprecedented [Au(S(2)O(7))(2)](-) anion in which a square planar coordination of the central gold atom is achieved by the chelating attachment of two disulfate groups. The disulfates were characterized by means of IR spectroscopy and DTA/TG measurements. For both compounds, the decomposition occurs via several steps and is finished at about 450 °C at the stage of elemental gold and the sulfates M(2)SO(4) (M = Li, Na), as revealed by X-ray powder diffraction of the residues.  相似文献   

19.
Limitations on current methodologies for the introduction of CF(2) and CFH in complex alpha-fluorophosphonates led to the synthesis of a fluorine-containing building block TIPS-C&tbd1;CCFXP(O)(OEt)(2), where X = H or F. This multifunctional fluorine synthon reacts with carbonyl compounds under WHE conditions to give high yields of fluorinated conjugated enynes and enediyne. When X = F, trapping of the desilylated anion with an electrophile after TIPS removal provided exclusive access to gamma-substituted derivatives of alpha-fluorophosphonates. When X = H, TBAF deprotection of the silyl group yields H(2)C=C=CFP(O)(OEt)(2) through an allenyl-propargyl resonance stabilized anion. The allene moiety has been used as template in the stereoselective synthesis of alpha-fluoro-beta, gamma-diiodopropenyl phosphonate, via electrophilic iodination, and alpha-fluoro-gamma-amino-alpha,beta-unsaturated phosphonates, including unsaturated phosphononucleosides, by nucleophilic displacement of an allylic iodide. Hydroamination of H(2)C=C=CFP(O)(OEt)(2) using secondary amines produced (Z)-alpha-fluoroenaminophosphonates, whereas Diels-Alder cycloaddition with cyclopentadiene provides the corresponding exocyclic vinylfluorophosphonate.  相似文献   

20.
The title compound 3-(2,4-dichlorophenyl)-4-dydroxy-3-(2,4-dichlorophenyl)-4- dydroxy-5-cyclohexanyl-A3-dihydrofuran-2-one 5 has been synthesized by the cyclization of methyl O-(2,4-dichlorophenyl-acetyl)-1-hydroxycyclo-hexane-carboxylate 4, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group Pi with a = 6.8192(3), b = 10.5053(5), c = 10.5811(5)A,α = 71.681(10), β = 78.905(12), γ = 81.036(12)°, C15H14C1203, Mr = 313.18, V= 702.44(6)A3, Z = 2, De= 1.481 g/cm^3, F(000) = 324,μ = 0.465 mm^-1, S = 1.006, the final R = 0.0331 and wR = 0.1363 for 2505 observed reflections with I 〉 2σ(I) and 183 variable parameters. The crystal analysis shows that the cyclohexene unit of the title compound has a quasi-chair conformation, and a one-dimensional chain structure is formed via the intermolecular hydrogen bond O(1)-H(101)…O(2).  相似文献   

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