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1.
The reaction of optically active O-ethyl O-phenyl phosphorochloride 1 with alcohol, phenol,amine, mercaptan or thiophenol, respectively, in the presence of an alkali obtained optically activeO-ethyl O-phenyl phosphorothioic derivatives 2 with inversion of configuration. The hydrolysis of 2was carried out in 1 N NaOH-dioxane solution. The hydrolysis of 2a and 2h predominantly gaveproducts with inversion of configuration with OPh as leaving group, but also gave products withretention of configuration with OMe or SPr as leaving group. Exclusive products with inversion ofconfiguration with OPh as leaving group were only obtained from the hydrolysis of 2b, 2f and 2g.The hydrolysis of 2c gave product with inversion of configuration with OC_6H_4NO_2-p as leavinggroup. From 2d, 2e and 2i, products with retention of configuration were formed with OC (Me)-CHCO_2 Et(Z), OC(Me)-CHCO_2Et(E) and SPh as leaving group, respectively. All the above resultscan be satisfactorily interpreted in the light of trigonal bipyram  相似文献   

2.
The Grignard reagents with the retention of configuration and partial isomerizationare formed in the reactions of Z- and E-β-bromostyrene with magnesium in THF. Sty-tene, phenylacetylene and E,E-diphenylbutadiene-1,3 are produced as byproducts. Whenthe reaction of Z-β-bromostyrene with magnesium was carried out in THF-d_8, CIDNPeffects were observed for the products of Z-β-styrylmagnesium bromide, E-β-styrene-dand E, E-diphenylbutadiene-1,3. According to the CIDNP and the products obtainedfrom the reactions of these two Grignard reagents with carbon dioxide, it is proposedthat a free radical mechanism, initiated by one electron transfer from magnesium to β-bromostyrene, is involved in the formation of β-styrylmagnesium bromide. The investi-gation on the reactions of the title Grignard reagents with trityl chloride showed thatvinylic Grignard reagent radical cation formed in ET reaction can undergo β-hydrogenmigration. The different distribution of AA, AB and BB types of products obtainedfrom the  相似文献   

3.
This paper reports the crystal and molecular structure of title compound. 3978 three-dimensional independent reflections were collected by Syntex R3 four circle diffractometer. The crystal is monoclinic with space group P2_1, a=8.074(1), b=11.309(4), c=27.793(9), β=106.84°(2), Z=4. The molecular formula is Pt(C_8 H_(15)O_4N)_a Cl_2. The crystal structure was solved by Patterson method and refined by block matrix least squares refinement techniques. The final R factor is 0.039.The result of crystal structure analysis shows that Pt(Ⅱ) has a dsp~2 hybrid orbital and square coordination. Two C1 atoms are located oppositely to two diethyi-dichloride-di-L-aspartare. N atoms have sp~3 tetrahedral hybrid configurations and form the coordinate bonds with Pt(Ⅱ) atom using their lone pair electrons. By reason of molecular packing and due to the formation of inner hydrogen bonds in the complex molecule, the configuration of L-aspartic acid in the title complex is more twisted than that of L-and DL-aspartic acid  相似文献   

4.
The title compound forms black crystals shaped like pseudo-octahedrons, which belong to the orthorhombic system The space group is Pna 2_1 with unit cell parametrs of a=17.815(1), b=16.629(2), c=12.003(1), and with Z=4, D_(obs)=1.80g·cm~(-3), and D_(calc)=1.804g·cm~(-3). The crystal structure was solved by the heavy atom method and refiened by fullmatrix least-squares to a final conventional R factor of 0.048 for 2584 unique reflections with I≥σ(Ⅰ). The investigation confirms that the crystal structure consists of tetraethylammonium cations and trinuclear Mo cluster anions. The anion is a μ_3-O monocapped trinuclear cluster with an average Mo-Mo bond length of 2.60 (2). On the side of the Mo_3 triangular plane opposite to the μ_3-O atom, each two Mo atoms are bridged by a Cl atom with the result that these seven atoms (3 Me, 1 O and 3 Cl atoms)form an apex-deficient quasicubane configuration. In addition, each Mo atom is coordinated to three additional atoms resulting in a pseudo-octahedral geome  相似文献   

5.
The reaction of N-substituted-benzenesulfonyl-N'-(4,6-disubstituted-s-triazin-2-yl)-ethylene diamines with tri(dialkylamine)phosphine has been studied and the cyclic products have been obtained by one-pot reaction. It was found from ~1H NMR and ~(13)C NMR analyses that the single bond rotation between the nitrogen atom 3 in the 1,3,2-diazaphospholidines and the carbon atom 2 in the s-triazine was hindered at room temperature, which was further confirmed by X-ray diffraction results. The most stable conformation of the phosphorous heterocycle is envelope-form. From the bond length and the hybridization of the nitrogen atom outside the ring, it was deduced that there was a certain contribution of dπ-pπ bond between P and N atoms.  相似文献   

6.
The optical anisotropy index is a new conception which has been proposed by the author of this paper on the basis of the Gladstone refractivity (i.e. specific energy by Larsen). The conception is very useful for studying the structural-optical mineralogy. The polarizability ellipsoid of atom groups in minerals may be obtained from the optical anisotropy index; conversely, when the crystal structure, orientation, and the polarizability ellipsoid of atom groups are known, the optical anisotropy index of the minerals may be calculated, and then three principal refractive indices, and the optical axis angles may be calculated, too. The calculated values of optical properties are in very good agreement with the experimental values. This calculation method is much simpler thanBragg's for the carbonates, and the precision of calculated values is much higher than that of Bragg's. The principle of calculation method is suitable for all the minerals containing some strong anisotropic atom groups, besides carbonat  相似文献   

7.
The title compound has been synthesized by the reaction of sodium α-dithionaphthoatewith CuCl_2 in an alkaline aqueous solution or by the reaction of α-dithionaphthoic acid withCuCl_2 in an organic solvent, The crude product was recrystallized in a mixture of CS_2 andC_2H_5OH. The crystals obtained are red and stable in air. The structure of the title compound is determined by a single-crystal X-ray diffractionanalysis. The crystal belongs to monoclinic space group C_(2h)~5- P(2_1/a) with unit cell parameters:a= 16.453(3)A, b=12.651(4)A, c=23.182(7)A, β=100.5(2)°, V=4744.6A~3,Z=4. Thestructure was refined to R=0.06 for 4707 reflections. In the molecule, Cu_4 cluster has a distorted tetrahedral configuration. Surrounding thistetrahydron are four α-perthionaphthoate ligands, coordinated to copper through the sulfuratoms. One of the sulfur atoms in each ligand forms sulfur bridge with copper atoms,while the other is coordinated to only one copper. The three Cu--S bonds formed by thethree sulfur atoms with a given copper atom are approximately coplanar. Each group--C--S_2 with Cu atom on a vertex of the tetetrahedron forms a five-member ring. Thesefive-member rings are also approximately cooplanar. The molecule possesses an approachingS_4 point symmetry. The mechanism for the formation of the title compound involves a redox reaction.which is discussed in this paper.  相似文献   

8.
<正> A new quantitative relationship between the coupling constants 3JH-H of substituted ethylenes and the electronegativities Ex of the substi-tuents has been proposed. It can thus be conveniently used to estimate the values of 3JH-H of substituted ethylenes, thereby identifying the type of substituents and determining the molecular configuration of disubstituted ethylenes. It is shown from the calculations of 664 3J values carried out for 414 compounds that the standard deviation between the calculated and the experimental values is 0.26 Hz.In addition, it also provides a new method for determining the electronegativities of functional groups.The electrone-gativity data of 98 substituents determined so far suffice to indicate that most of them agree fairly well with Pauling's or revised Pauling's electrone-gativity data of a atoms in the substituents.  相似文献   

9.
Cu(en)_2Ag(SCN)_3 crystallizes in space group P2_12_12_1 with its cell parameters, a=7.126(2), b=12.587(5), c=17.585(5). There are four formula units per unit cell(ρ_obs.=1.90g/cm~3, ρ_(calc.=1.96g/cm~3). Diffraction data are collected on a CAD4 four-circle diffractometer using Mo-Ka radiation. The structure is determiued by heavy atom method, then refined by leastsquare method to a final R=0.036. It is shown that in the crystal the coordination of Cu atoms is square pyramidal with four N atoms of en groups in the square plane and oue Natom of thiocyanate group in the apical position. The Ag atom is coordinated tetrahedrally by four S atoms of thiocyanate groups, one of which links up two AgS_4 together, thus forming the infinite AgS_4 tetrahedron chains along a axis.  相似文献   

10.
The oxidation-reduction reaction of the molybdenum cluster compound Mo_3(μ_3-S)(μ-S)_2-[μ-SOP(OEt)_2] [S_2P(OEt)_2]_3(O)_2 with CuCl_2·2H_2O has been investigated and the chemical components of its product, Cu_8Cl_2[S_2P(OEt)_2]_6, were confirmed. The crystal belongs to the triclinic system and the space group is P with the following unit cell parameters: a=11.578 (5), b=12.663 (3), c=14.317 (4); α=55.54 (2)°, β=57.35 (3)°, γ=72.23 (3)°; Z=1; D_(calc)=1.926 g·cm~(-3). Final discrepancy factor of R is 0.075 for 3573 unique reflections with I≥3σ(I). The results of investigation show that the crystal structure consists of molecular chains with Cu_8Cl_2[S_2P(OEt)_2]_6 as structural unit, in which eight Cu atoms form a cube-shaped cage. The coordination sphere of each Cu atom is a tetrahedron configuration. The distances between Cu atoms are 3.018-3.437, which indicates that there are no metal-metal bonds between Cu atoms. It is worthwhile to study further the phenomenon how Cu(+2) captures the  相似文献   

11.
The mixed ligand complex of cobalt with dibutylphosphate (HDBP) and pyridine has been synthesized. Elemental analysis yields the result that the formula of this compound is Co(DBP)_2·3Py·CHCl_3 (Py=pyridine). The thermal analsyis, visible spectra and magnetic properties of it have been studied as well. Single crystal structural analysis shows that the crystal is triclinic with space group P and the unit cell parameters are as follows:a=14.490(10), α=90.37(4)°,b=15.721(7), β=96.04(5)°,c=20.109(12), γ=105.63(4)°.The final R factor is 0.0773. Two Co atoms are connected by two bridging DBP groups to form a dinuclear molecule [Co(DBP)_2·3Py]_2 which has a C_s, symmetry. Each cell contains two dinuclear molecules and four chloroform molecules. The cobalt is coordinated in an octahedral arrangement by three oxygen atoms and three nitrogen atoms, of which one oxygen atom comes from a monodentate DBP group, two oxygen atoms from two bridging DBP groups, and the three nitrogen atoms from the three pyridi  相似文献   

12.
A new series of dextrorotatory derivatives of 1R,3RS,5S-1,8,8-trimethyl-2,4,3-diazaphosphabicyclo [3.2.1] octane with a newly formed chiral phosphorus atom has been prepared by an asymmetric reaction of (+)-cis-1R,3S-1,2,2-trimethyl-1,3-cyclopentadiamine with some thiophosphoryl dichlorides. The optically active products consisted of two unequal amounts of diastereomers,(1R, 3R, 5S) isomers and(1R, 3S, 5S) isomers. Two regioselective reactions took place when phenoxy thiophosphoryl dichloride and N,N-dialkylamino thiophosphoryl dichlorides were chosen as the reagents for the reaction. The content of (1R, 3R, 5S) isomers in the product was over 90% for the former and there were only (1R, 3S, 5S) isomers obtained for the latter.  相似文献   

13.
Praelolide is a new compound which was isolated out from the gorgonian, Menella praelonga (Ridley), collected from the South Sea of China at Zhanjiang, Guangdong. The molecular formula is C_(28) H_(35) O_(12)C1. The research result by X-ray diffraction method on the crystal structure is presented. The compound is orthorhombic with space group P2_12_12, cell dimensions α=16.936, b=16.709, c=10.333, and Z=4. The structure has been solved by direct method and refined to R=0.055 for 2257 unique observable reflexions by least-squares. The molecule is composed of the major conformational isomer in which the three main rings(a six-membered ring, an eight-membered ring, a six-membered ring) take separately the form of chair-chairboat-chair, a five-membered actone ring, a C1 substitution, 4 acetate groups, and a three-membered epoxide ring. The absolute configuration of the molecule has also been determined by statistics (R factor ratio =1.012) and Bijvoet pairs observation. For 30 pairs of the greatest anomalo  相似文献   

14.
On the assumption that the salt effect (salting-out or salting-in) representsthe balance of the electrostatic effect between the ion and the water dipole andthe dispersion effect between ion and nonelectrolyte molecule, the solubilitiesof n-valeric acid in five cobaltammimes were studied and reported in article Ⅰof this series. In the present investigation the activity coefficients of naph-thalene in two series of salts are determined spectrophotometrically. The firstseries consists of seven sodium salts of fatty acids (sodium formate to sodiumn-heptylate), differing from one another only by the number of CH_2 groups inthe anions. The second series consists of ammonium bromide and three tetra-  相似文献   

15.
The X-ray photoelectron spectra of sixteen derivatives of N-β-phenethyl amine and N-β-phenethyl glycine have been studied. The effect of different structures on N_(1s) binding energy and that of their Pauling's atomic charge density on the nitrogen atoms are investigated. The experimental binding energy of N_(1s) is proportional to the calculated Pauling's atomic charge density. It shows that the phosphoryl group is the strongest nitrogen lone pair electron localizing group as compared with the corresponding sulfonyl and acyl derivatives. The XPS results agree with the data that there is no decarbonylation during the synthesis of N-dialkylphosphoryl-tetrahydro-3-benzazepin-l-one.  相似文献   

16.
The attachments of phycobilins to cysteinyl residues have been worked out through the reactions of phycoerytbrobilin dimethyl ester and phycocyanobilin dimethyl ester with cysteine methyl ester and reduced glutathione dimethyl ester respectively. A series of model compounds which carry the same conjugative skeletons as the chromophores in phycobillproteins have been purified anti identified. These compounds are characterized with strong fluorescence emission and circular dichroism effects which appeared weaker for the common bilinoid chromophores. Analyses of the circular dichroism effects of these compounds indicated that the major reaction products of phycobilins with cysteine methyl ester and reduced glutathione dimethyl ester carried the same stereochemical configuration as the chromophores in phvcobilinoroteins  相似文献   

17.
O-Aryl O-ethyl N-isopropyl phosphoramidothioates (Ⅰ) have herbicidal activity. In order to study the relationship between structures and activities of these compounds, more than thirty compounds (Ⅰ) have been prepared by the reaction of O-aryl O-ethyl phosphorochloridothioates with isopropylamine in the presence of 40% NaOH at 0℃. The intermediates, phosphorochloridothioates, were prepared separately from a large excess of O-ethyl Phosphorodichloridothioate and various substituted phenols in the presence of 40% NaOH and a catalyrical amount of Et_3N at 0—5℃. As a result, higher purity and good yields were obtained.It was found that the activity of these compounds was highly dependent upon the substituents attached to the benzene ring with respect to the characteristic parameters π, E_s, σ and F by using Hansch's equation.It was indicated that hydrophobic (π), steric (E_s), and electronic (σ and F) effects of the substituents on the ring in those molecules seem to be of considerable importance i  相似文献   

18.
<正> The crystal structure of the title compound has been determined. PdC52H44N2P4, Mr = 927. 2, monoclinic, space group P21 /n, a =12. 102(2), b = 9.997(2), c=20. 254(5)(?),β=93. 80(2)°, V = 2445. 0(?)3, Z = 2, R =0. 075 and Rw = 0. 095 for 3535 observed reflections (I>3σ(I)), The palladium atom is located on the symmetric center and adopts a square planar coordination surroundings with two biphosphine ligands and two cyanide groups. The molecular structure in crystals is different from that in solution in which the molecule is very fluxional, probably due to the rapid alteration in coordination sites between the coordinated and uncoordinated phosphorus atoms of the biphosphine ligands. Their properties are also reported.  相似文献   

19.
The title crystal is straw-yellow in colour, belonging to the triclinic system. The space group is P with the following unit cell parameters:a=11.570(2), b=13.093(1), c=14.399(2), α=102.62(1), β=102.15(1), γ=111.87 (1)°, V=1870(1), Z=2, D_(calc)=1.960g·cm~(-3).The crystal structure was solved by the heavy atom method and refined by full-matrix least-squares to a final conventional R factor of 0.055. The results show that the crystal structure consists of neutral trinuclear Mo cluster molecules, in which three independent Mo atoms form an equilateral triangle with an average side length of 2.725(3), corresponding to a Me-Me single bond. On one side of the triangle one μ_3-S atom binds the three Mo atoms together to form a monoeapped trinuclear cluster. In addition, three S_2 radicals acting as μ_2 bridges are located between each two Mo atoms. Each Mo atom is also coordinated to two terminal S atoms of an [S_2P(OEt)_2]~- radical so as to complete a distorted pentagonal bipyramid configuration.  相似文献   

20.
The amino acids' side chains act as the relay device to modulate the chemical reactivity of the N-phosphoryl amino acids. The N-dialkyl phosphoryl cysteine is stable, but the N-dialkyl phosphoryl serine or threoine was converted into many kinds of products at 40℃. The N-dialkyl phosphoryl gltamic acid is a stable compound, while the N-dislkyl phosphoryl aspartic acid was transferred into the peptides, esters and the phosphoryl ester-exchanged products under mild conditions. The N-dialkyl phosphoryl histidine has the similar reactivity through the co-participation of the side chain, carboxyl and phosphoryl groups. A hexacoordinate phosphorus was proposed to account for this differentiation and promotion effect.  相似文献   

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