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1.
赵尚勃  郑芊  谢军楷 《化学学报》1989,47(9):842-845
假设双齿杂环胺酞花菁铁(II)盐配合物(FePcL)n具有D4h对称性, 通过对其吸收谱分析, 得到了晶场参量Dq和配合物结构间的关系, 从而关联观测电导值和配合物结构,在谱分析中利用了减少可调参量数目的技巧, 以增加理论分析的可靠性。  相似文献   

2.
张文勤  王明真 《有机化学》1993,13(4):366-370
合成了8个反 -1,2-双[2-(5-取代苯基恶唑基)]环丙烷和2个1,2-双[2-取代苯基恶唑基)]乙烷,其中9个为新化合物.讨论了化合物的结构与其电子光谱及荧光量子产率间的关系.发现恶唑环与三元环间存在一定程度的共轭,并解释了上述化合物荧光量子产率较低的现象.  相似文献   

3.
Due to a facile head-to-tail [3+2] dimerization, even a sterically demanding group such as the Mes (2,4,6-tri-tert-butylphenyl) group around the PCC moiety did not allow us to isolate 3-(4-cyanophenyl)-1-(2,4,6-tri-tert-butylphenyl)-1-phosphaallene from the elimination reaction of 2-bromo-3-(4-cyanophenyl)-1-(2,4,6-tri-tert-butylphenyl)-1-phosphaprop-1-ene with DBU (1,8-diazabicyclo[5.4.0]undec-7-ene), and the corresponding 1,4-diphosphafulvene containing cyano groups was obtained and characterized. Theoretical studies on the [3+2] dimerization of phosphaallene characterize possible intermediates affording 1,4-diphosphafulvenes and also suggest the cyano group effect to facilitate the saturation of the PC double bonds. On the other hand, 1,2-bis(4-cyanophenyl)-3,4-bis[(2,4,6-tri-tert-butylphenyl)phosphinidene]cyclobutene was obtained from 2-bromo-3-(4-cyanophenyl)-3-trimethylsiloxy-1-(2,4,6-tri-tert-butylphenyl)-1-phosphaprop-1-ene together with the 3-(4-cyanophenyl)-1-phosphaallene.  相似文献   

4.
Mono- and Bis(difluorophosphoranyl)ethylene, n-Hexylidene-fluorophosphorane, and a 2,4-Di-n-pentyl-1λ5, 3λ5 -diphosphete Bis(diethylamino)phosphanylethylene, 1 , is converted by SF4 into bis(diethylamino)difluorophosphoranylethylene, 2. Analogously trans-1,2-bis(diphenylphosphanyl)ethylene, 3 , is converted into trans-1,2-bis(difluorodiphenylphoranyl)ethylene, 4. 2 reacts with n-butyllithium to give n-hexylidene-bis(diethylamino)fluorophosphorane, 5. With more n-butyllithium, the main product n-hexylidene-bis(diethylamino)-n-butylphosphorane, 7 , and the by-product 2,4-di-n-pentyl-1,1,3,3-tetrakis(diethylamino)-1λ5, 3λ5 -diphosphete, 8 , are formed. With t-butyllithium 2 yields 3,3-dimethyl-butylidene-bis(diethylamino)fluorophosphorane, 6. All new compounds 1, 2, 4–8 are characterized by their nmr and ir spectra.  相似文献   

5.
Dioxygen addition to the 16-electron complexes [OsX(P-P)2]+ (3) gives the dioxygen adducts [OsCl(eta 2-O2)(P-P)2]+ (3), which in turn react with HCl gas to give the novel osmium(IV) oxo complexes trans-[OsX(O)(P-P)2]+ (5) (X = Cl, Br; P-P = 1,2-bis(dicyclohexylphosphino)ethane (dcpe), 1,2-bis(diethylphosphino)ethane (depe), 1,2-bis((2R,5R)-2,5-dimethylphospholano)benzene (Me-duphos)). The complexes [OsX(dcpe)2]+ (X = Cl, Br) (3) are studied by X-ray crystallography and are shown to have a "Y-shaped" coordination geometry in the equatorial plane. The X-ray structural analysis of [OsCl(eta 2-O2)(dcpe)2]+ (4a) reveals an exceptionally short O-O bond (1.315(5) A). trans-[OsCl(O)(dcpe)2]+ (5a), the first oxo complex of osmium(IV) investigated crystallographically, exhibits a long Os-O distance of 1.834(3) A. The reactivity of 4 and 5 as oxidants is described. The dioxygen complex 4a transfers one oxygen atom to PPh3 (to give Ph3PO) or oxidizes iodide ions to triiodide ions in the presence of anhydrous HCl. In both reactions, the corresponding oxo species 5a is quantitatively formed as the only metal-containing product. Oxo complexes 5 are surprisingly stable and unreactive toward standard reducing agents such as phosphines.  相似文献   

6.
A coordination assembly of 3,5-dinitro-4-methylbenzoic acid and Pr(III), synthesized by hydrothermal methods forms a host structure, which is stable up to 300 [degree]C, through C-HO hydrogen bonds and accommodates different types of guest species varying from simple molecules like water to larger molecules like trans-1,2-bis(4-pyridyl)ethene.  相似文献   

7.
作为相互识别的结果,(±)-2,2′-二羟基-1,1′-联萘酚可与4,4′,6,6′-四甲基-2,2′-联嘧啶、1,2-双(4-吡啶)乙烷、反式-1,2-双(4-吡啶)乙烯、4,4′-联吡啶-N,N′-双氧化物及双-2-吡啶基甲酮等多种含氮化合物分别形成外形良好的共晶化合物1,2,3,4及5.本文对5个共晶化合物的晶体...  相似文献   

8.
A periodic mesoporous MCM-41 organosilica containing trans-1,2-bis(4-pyridyl)ethylene (t-BE) (350 m2 g-1; 0.28 cm3 g-1) incorporated in the silica walls undergoes photochemical isomerization to the cis configured bis(4-pyridyl)ethylene resulting in a dramatic area (473 m2 g-1) and pore volume (0.38 cm3 g-1) increase.  相似文献   

9.
The controlled colour generation and colour erasing phenomena of alkylammonium polyoxomolybdate complexes were first observed in the trans-(1R,2R)-1,2-bis(undecylcarbonylamino)cyclohexane organogel system using the sol-gel phase transition.  相似文献   

10.
Template induced photodimerization of trans-1,2-bis(n-pyridyl)ethylene dihydrochlorides and trans-n-stilbazole hydrochlorides within cucurbit[8]uril in aqueous media leads to high yields of the syn dimer.  相似文献   

11.
本文合成了8个反-1,2-双[2-(5-取代苯基恶唑基)]环丙烷和2个1,2-双[2-(5-取代苯基恶唑基)]乙烷,其中9个为新化合物。讨论了化合物的结构与其电子光谱及荧光量子产率间的关系。我们发现恶唑环与三元环间存在一定程度的共轭,并解释了上述化合物荧光量子产率较低的现象。  相似文献   

12.
Direct trimethylsilylation of naphthalene under certain condition has been found to afford substitution as well as addition products: 1-and 2-trimethylsilylnaphtalene (I, II), 1-trimethylsilyl-1,4-dihydronaphthalene (III), trans-1,2-bis(trimethylsilyl)-1,2-dihydronaphthalene (IV-a) and its isomer (IV-b), and 1,2,4-tris(trimethylsilyl)-1,2-dihydronaphthalene (V). The configuration has been determined by nmr spectroscopy, and the possible reaction path was proposed.  相似文献   

13.
A new total synthesis of (+)-7-deoxypancratistatin 1 has been accomplished in 19 steps (8% overall yield) from two readly available compounds, furan and trans-1,2-bis(phenylsulfonyl)ethylene.  相似文献   

14.
The kinetics study of the oxidative decolorization of Acid-Blue 92 has been investigated by hydrogen peroxide catalyzed with bimetallic metal-organic frameworks. The used metal-organic frameworks (MOF) are [Ph3SnCu(CN)2·L] where L=pyrazine (pyz) 1, methylpyrazine (mepyz) 2, 4,4'-bipyridine (bpy) 3, trans-1,2-bis(4-pyridyl)ethene (tbpe) 4 or 1,2-bis(4-pyridyl)ethane (bpe) 5. The reaction was followed by conventional UV-Vis spectrophotometer at λmax=571 nm. The reaction exhibited first-order kinetics with respect to [dye] and [H2O2]. The reactivity of the catalysts depends on the type of the medium and thereafter decreases in strong alkaline media. Addition of NaCl enhances the reaction rate. Also, the irradiation of the reaction with UV-light enhanced the rate of AB-92 mineralization by about 86.9%. The reaction was entropy-controlled as confirmed by the isokinetic relationship. A reaction mechanism was proposed with the formation of free radicals as an oxidant.  相似文献   

15.
Co-crystallization of 1,8-naphthalenedicarboxylic acid (1,8-nap) with trans-1,2-bis(n-pyridyl)ethylene (n,n'-bpe) (n = 2 or 4) yields a discrete four-component molecular assembly, 2(n,n'-bpe).2(1,8-nap) 1, that is held together by four O-H...N hydrogen bonds where the dicarboxylic acid, serving as a linear template, directs alignment of olefins in the solid state for [2 + 2] photoreaction.  相似文献   

16.
合成了3种新型1,1-二(2-苯并咪唑基)-2-苯基乙烯衍生物——1,1-二(2-苯并咪唑基)-2(4-氰基苯基)乙烯(1)、1,1-二(2-苯并咪唑基)-2(4-甲氧羰基苯基)乙烯(2)和1,1-二(2-苯并咪唑基)-4-苯基-1,3-丁二烯(3),通过核磁共振氢谱和碳谱(1H、13C NMR)、质谱(MS)对它们进行了结构表征。用紫外可见吸收光谱(UV-V is)和荧光发射光谱测定了该阳离子受体与不同金属离子(Zn2 、Cd2 、Hg2 和Cu2 )的络合选择性。结果表明:该荧光受体对Zn2 、Cd2 、Hg2 和Cu2 均具有较高的选择性和荧光响应。  相似文献   

17.
The molten reaction of 2-naphthol, 4-(aminomethyl)pyridine, and 4-pyridinecarboxaldehyde at about 180 degrees C yields trans-2,3-dihydro-2,3-di(4'-pyridyl)benzo[e]indole (1) which possesses two chiral centers, rather than an expected Betti-type reaction product with only one chiral carbon center. The same reactions, using 3-pyridinecarboxaldehyde, 4-cyanobenzaldehyde, or 3- cyanobenzaldehyde instead of 4-pyridinecarboxaldehyde produce the related compounds trans-2,3-dihydro-2-(4'-pyridyl)-3-(3"-pyridyl)benzo[e]indole (2), trans-2,3-dihydro-2-(4'-pyridyl)-3-(4"-cyanophenyl)benzo[e]indole (3), and trans-2,3-dihydro-2-(4'-pyridyl)-3-(3"-cyanophenyl)benzo[e]indole (4), respectively. This reaction proceeds with a high degree of stereoselectivity with a trans/cis ratio of about 98:2 at elevated temperature. Compounds 1, 2, and 4 crystallize in a noncentrosymmetric space group (Pca2(1), Pca2(1), and Cc), while compound 3 has a chiral space group (P2(1)). These successfully acentric packing arrangements are probably due to the molecule bearing both two chiral centers and potential hydrogen-bonding groups. Furthermore, the reaction of racemic 6-hydroxy-2'-methyl-2-naphthaleneacetic acid with ethyl-2-cyano-1-(4'-pyridyl)acrylic acetate in the presence of piperidine gives 1-pyridyl-2-ethoxycarbonyl-3-amino-1H-naphtho[2,1-b]pyran-2'-methylacetic acid (5), which likewise crystallizes in a chiral space group. All of compounds are second harmonic generation (SHG) active, and have a very strong SHG response approximately about 8.0, 5.0, 12.0, 6.0, and 1.4 (for 1-5 compounds) times that of urea. Ferroelectric property measurements indicate that compounds 1, 2, 4, and 5 may display ferroelectric behavior.  相似文献   

18.
The frustrated Lewis pair B(C(6)F(5))(3)/P(o-tolyl)(3) (4a) reacts with 4,6-decadiyne to give the trans-1,2-addition product 5. In contrast, the B(C(6)F(5))(3)/P(t)Bu(3) FLP (4b) reacts with this substrate to give the trans-1,4-adduct trans-6. The cumulene trans-6 undergoes trans-/cis-isomerization upon photolysis to give a ca. 1:1 trans-6/cis-6 mixture. The FLP 4b reacts with 2,6-hexadiyne at r.t. to yield a ca. 4:1 mixture of their trans-1,2- and trans-1,4-addition products (7,8). DFT calculations showed that the zwitterionic 1,4-addition products are favored under thermodynamic control. Thermolysis of the kinetic trans-1,2-addition product (7) (80 °C, bromobenzene) does not lead to the thermodynamically favored 1,4-isomer (8), but instead elimination of isobutylene occurs to the formal trans-1,2-adduct (9) of the B(C(6)F(5))(3)/PH(t)Bu(2) pair. Compounds 5, 6, 7, 8, 9 were analyzed by X-ray diffraction.  相似文献   

19.
Reaction of 1,2-diacetoxy-1,2-bis(acylamino)ethanes with acetamide and urethane gave rise to 1,2-bis(acetylamino)-1,2-bis(acylamino)ethanes and 1,2-bis(acylamino)-1,2-bis(ethoxycarbonylamino)ethanes respectively. Condensation products were isolated of reactions between 1,2-diacetoxy-1,2-bis-(acylamino)ethanes with acetonitrile, diaminofurazan, and 4-phenylfurazan-3-ylamine.  相似文献   

20.
A series of novel chiral diphosphite ligands have been synthesized from (1R,2R)-trans-1,2-cyclohexanediol, (1S,2S)-trans-1,2-cyclohexanediol, racemic trans-1,2-cyclohexanediol and chlorophosphoric acid diary ester, and were successfully employed in the Cu-catalyzed asymmetric 1,4-conjugate addition of diethylzinc to cyclohexenone with up to 99% ee. It was found that ligand 1,2-bis[(R)-1,1'-binaphthyl-2,2'-diyl]phosphitecyclohexanediol 6a derived from racemic diol skeleton can show similar catalytic performance compared with ligand (1R,2R)-bis[(R)-1,1'-binaphthyl-2,2'-diyl]phosphitecyclohexanediol 6a' derived from enantiopure startingmaterial. A significant dependence of stereoselectivity on the type of enone and the ring size of the cyclic enone was observed. Moreover, the configuration of the products was mainly determined by the configuration of the binaphthyl moieties of diphosphite ligands in the 1,4-addition of cyclic enones.  相似文献   

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