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1.
A practical protocol to obtain 1,1'-binaphthyl-2,2'-diamine was developed from 2-naphthol and 2-naphthylhydrazine under mild conditions:solvent-free,125-130℃,atmospheric pressure.The convenient procedure makes the process amenable for large-scale synthesis of the versatile compound.  相似文献   

2.
A convenient synthesis of chiral 3,3′-disubstituted 1,1′-binaphthyl-2,2′-disulfonic acids (BINSA, 1) was developed. The key was directed ortho-lithiation of BINSA methyl ester 2 with n-BuLi and subsequent reaction with an electrophile. Electrophiles such as Br2, I2, Me3SiOTf, and i-PrOB(Pin) reacted smoothly with 3,3′-dilithiated BINSA methyl ester, and the corresponding 3,3′-dihalo-, 3,3′-bis(trimethylsilyl)-, and 3,3′-diboryl-BINSA derivatives were obtained in yields of 21–78%. This simple synthetic method is highly attractive since the ability to prepare 3,3′-disubstituted BINOLs in advance can be useful.  相似文献   

3.
Crystal determination of a complex between 2,6-dimethoxyflavone and perchloric acid revealed that the inclusion compound contains a water of crystallization that participates in hydrogen bonds connecting the perchloric anion and the carbonyl oxygen of the flavone. The torsion angle between the-benzopyrene and the phenyl rings O(1)C(2)C(1)C(6) is –45, which gives a less twisted molecule than the parent molecule or other inclusion compounds with carboxylic acids. A comparative study with these structures shows that the hydrogen bond forces coplanarity between the-benzopyrone and phenyl rings.  相似文献   

4.
Abstract

Crystal structure analysis of the imidazole associates with 1,1′-binaphthyl-8,8′-dicarboxylic acid (1), [1a, triclinic, P1, a = 7.569(4), b = 8.393(2), c = 8.634(1) Å, α = 93.21(2), β = 106.88(3), γ = 105.17(3)°, Dc = 1.36 g/cm3, Z = 1, R = 0.045 for 1031 data] and with 2,2′-dihydroxy-1,1′-binaphthyl (2), [2a, tetragonal P41212, a = 8.519(1), c = 29.821(2), Dc = 1.30 g/cm3, Z = 4, R = 0.051 for 1236 reflections] revealed 1:1 and 1:2 stoichiometry, respectively. Spontaneous resolution occur during crystallization in both compound crystals. 1a is a salt-like associate with hydrogen bonds between the carboxylate and imidazolium ion pairs while the neutral 2a has also well defined hydrogen bonds between host and guest molecules. In a modeling experiment corresponding Brookhaven Protein Data Bank atomic coordinates from the active site of the bacterial serine protease enzyme Subtilisin BPN were fitted to the crystal packing of the small molecule associate 1a crystal. The relative displacement of the ion pair components and a symmetry related carboxyl function in 1a has fair steric resemblance to similar moieties in the active site of Subtilisin (Δave = 0.24 Å for 9 fitted atoms). The agreement in the results of two fully independent and totally different (i.e. a native protein active site and an artificial small molecule associate) crystal structure determinations underlines the assumed conceptual similarity of crystals (“giant supramolecules”) to protein sequences optimized through evolution.  相似文献   

5.
《Tetrahedron: Asymmetry》2004,15(23):3805-3810
X-ray diffraction analysis revealed unexpected stereochemical features accompanying crystal self-assembly of the two title oligocarboxylic acids.  相似文献   

6.
Optically active aromatic ether ketone macrocycles containing 2,2′-dimethoxy-1,1′-binaphthyl-6,6′-diyl moieties were synthesized through electrophilic aromatic substitution reaction and stepwise nucleophilic aromatic substitution reactions. Structures of the resulting macrocycles were confirmed by NMR and matrix assisted laser desorption/ionization time of flight (MALDI-TOF) mass measurements.  相似文献   

7.
Using X-ray diffraction study of acetylbenzimidazole 2-acetylbenzimidazole 1′-phthalazinylhydrazone we confirmed that this compounds exists as the phthalazonehydrazone tautomer, as was suggested earlier on the basis of IR and NMR spectroscopy and quantum-chemical calculations.  相似文献   

8.
The [Pd(dpa)(tsser)] complex (1) is prepared from the reaction of PdCl2 and 2,2′-dipyridylamine (dpa) with 4-toluenesulfonyl-L-serine (tsserH2). This complex is characterized by spectral methods (IR, UV-Vis, 1H NMR, and luminescence), elemental analysis, thermal analysis (TG, DTA), and single crystal X-ray diffraction. X-ray structure determinations show that in this complex, PdII atoms are four-coordinated in a distorted square-planar configuration by two N atoms from a bidentate 2,2′-dipyridylamine ligand and one N atom and one O atom from a bidentate tsser2– ligand.  相似文献   

9.
An x-ray structural investigation of -cyanoacrylic acid has been carried out (R=0.058 on the basis of 767 reflections). The molecules in the crystal are joined by strong O–H...N hydrogen bonds in zigzag chains along the [101] direction. The relative arrangement of the double bonds of neighboring molecules does not satisfy the conditions for topochemical reactions in crystals of compounds with C=C double bonds, in agreement with the stability of the crystals of -cyanoacrylic acid toward illumination and prolonged exposure to x rays.A. N. Nesmeyanov Institute of Organometallic Compounds, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, pp. 139–143, March–April, 1991.  相似文献   

10.
The crystal structures of two uranyl nitrate complexes with 2,2′-6,2″-terpyridine (Trpy), [(UO (Trpy)-[(UO2)2(Trpy)2(OH)2][UO2(NO3)2(OH)2] · 2CH3OH (I) and [(UO2)2(Trpy)2(OH)2]2[UO2(NO3)3(H2O)](NO3)3 · 3H2O (II), were studied. Compound I consists of the centrosymmetric dimeric cations [(UO2)2(Trpy)2(OH)2]2+, the anions [UO2(NO3)2(OH)2]2?, and solvation methanol molecules. Complex II consists of dimeric cations [(UO2)2(Trpy)2(OH)2]2+, the complex anions [UO2(NO3)3(H2O)]?, nitrate anions, and water molecules of crystallization. The uranium atom in the [UO2(NO3)3(H2O)]? anion in II has an unusual coordination polyhedron representing a hexagonal bipyramid in which one oxygen atom in the equatorial plane is replaced by two atoms equidistant from this plane.  相似文献   

11.
Three new coordination polymers have been synthesized from 1,1′-biphenyl-2,2′-dicarboxylic acid (2,2-dpa), nitrogen-containing coligands and Mn salts under hydrothermal conditions. The X-ray crystal structures of all three complexes are presented. With the change of nitrogen-containing ligand, the structural features of the complexes also change. The complex prepared without a nitrogen coligand exhibits a one-dimensional covalent chain-like structure, composed of the rare pentanuclear Mn building unit. The complex with 4,4′-bipyridine as a secondary ligand shows a two-dimensional layer structure. With the chelating ligand 1,10-phenanthroline, a discrete molecular complex is synthesized. The magnetic properties of the complex with 4,4′-bipyridine in the temperature range 1.99–300 K are reported.  相似文献   

12.
We have previously reported the results of studies of the hydrogen bond nature in N-phenyl-N′-isopropyl-p-phenylenediamine by a quantum chemistry method and FTIR spectroscopy [1–3]. It is shown that the IR spectrum of N-phenyl-N′-isopropyl-p-phenylenediamine has IR bands in the vNH absorption region at 3380 cm−1 and 3400 cm−1 corresponding to the NH groups involved in hydrogen bonding.  相似文献   

13.
14.
A new dimeric compound [{UO2(μ-OH)(terpy)}2](ClO4)2·0.67CH3CN, containing an uranyl cation and a tridentate 2,2′:6′,2″-terpyridine (terpy) ligand, is synthesized from an acetonitrile solution of uranyl perchlorate and terpy. The crystal structure of the compound is determined by single crystal X-ray diffraction. The crystal structure shows the formation of symmetric and asymmetric cationic hydroxo-bridged uranyl dimers. The uranium atoms adopt a distorted pentagonal bipyramidal configuration with a UO4N3 coordination environment formed by two uranyl O atoms, three N atoms from the terpy ligand, and two O atoms from the hydroxide anions.  相似文献   

15.
1,1'-Binaphthyl-2,2'-dicarboxylic acid (1) forms crystalline inclusion compounds with 1-PrOH (2:1) andt-BuOH (1:1). X-ray crystal structures of the two inclusion compounds are reported. Crystals of1·1-PrOH (2: 1) show triclinic ( ) symmetry with the unit cell dimensionsa = 10.160(1),b = 14.050(2),c = 15.167(1) Å = 100.37(1), = 104.40(1), and =94.82(1)°. Crystals of1t-BuOH (1: 1) are monoclinic (P21/n) with the cell dimensionsa = 10.603(5),b = 14.377(4),c = 15.664(7) Å, = 104.24(4)°. In both structures, H-bonded loops involving host –000H functions and guest –OH groups establish the supramolecular association. They relate these coordinatoclathrates to previous alcohol inclusions of1. Due to the unusual 2:1 (host: guest) stoichiometry, additional dimer-like interactions between –000H groups of host molecules are found in the 1-PrOH inclusion compound. From the point of view of topology these structures can be referred to as channel inclusion compounds.  相似文献   

16.
A simple two-step, one-pot procedure based on the treatment of sodium 2-naphthoxide with bromine yields 1,1′-binaphthalene-2,2′-diol in a high yield and an excellent purity. The procedure is applicable also to preparation of the symmetrically disubstituted analogues.  相似文献   

17.
The title compounds 1 and 2 were prepared from the respective, inexpensive and readily available thiophenes via reaction with lithium and sulfur monochloride, followed by reduction with lithium aluminium hydride.  相似文献   

18.
Bis-imines of 2,2′-diaminodiphenylditelluride and 2-tosylamino (9a) and 2-hydroxybenzaldehyde (9b) were prepared and studied by X-ray diffraction, heteronuclear (1H, 13C, 15N, and 125Te) magnetic resonance, and quantum chemical calculations (Pbe1pbe/DGDZVP). According to the X-ray diffraction data, compound 9b in the crystal phase has nonsymmetrical structure: one of the tellurium atoms forms hypervalent bonding with the adjacent oxygen atom, while the second one is not involved in such interaction. The NMR study showed the symmetric molecular structure of imines 9a,b in DMSO-d6 with the tellurium atoms interacting hypervalently with the C=N nitrogen atoms.  相似文献   

19.
While seeking molecular precursors for ZnS films obtained by gas phase chemical deposition [1, 2] we synthesized mixed-ligand compounds ZnL(ROCS2)2 [R = i-Pr. /-Bu; L = 2,2′-bipyridyl (2,2′-Bipy), 1,10-phenanthroline (Phen)] [3]. The volatile complex Zn(2,2′-Bipy)(i-PrOCS2)2 was used as a precursor to obtain electroluminescent ZnS:Mn films [4]. According to XRD data, the compound Zn(Phen)(i-BuOCS2)2 is monomeric. The c.n. of zinc is six. The Phen and 1-B11OCS2 ions behave as cyclic bidentate ligands [3, 5]. It was assumed that other mixed-ligand complexes with Phen and 2,2′-Bipy have an analogous structure [3]. Here we report on the structure of the known mixed-ligand complex of zinc(II) ethylxanthate with 2,2′-bipyridyl [6, 7]. It was found that the behavior of alkylxanthate ligands in mixed-ligand complexes of zinc(II) is more complex. Translated from Zhumal Stmktumoi Khimii, Vol. 41, No. 1, pp. 196-201, January–February, 2000.  相似文献   

20.
《Tetrahedron: Asymmetry》2014,25(23):1527-1531
A palladium-catalysed aminocarbonylation of a steroidal iodoalkene (17-iodo-5α-androst-16-ene) model compound with 2,2′-diamino-1,1′-binaphthalene as an N-nucleophile was carried out. The combination of a steroidal skeleton possessing central elements of chirality and a binaphthyl moiety with axial chirality was carried out resulting in a novel type of steroidal carboxamides. The binaphthalene—steroid conjugates are potential 5α-reductase inhibitors. Both epimers of the monocarboxamide and those of the dicarboxamide, formed with moderate diastereoselectivity, were isolated and fully characterised.  相似文献   

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