首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
3-(Trichlorogermyl)propanoic acid (la) reacts with phenylmagnesium bromide in malar ratio 1:4 to give 3-(triphenylgermyl)propanoic acid (2a).In the compounds la and 2a theβ-carboxylic functional group shows some unusual properties when they react with excess of phenylmagnesium bromide.The compound la reacts with phenylmagnesium bromide in molar ratio 1:5 to give phenyl 2-(triphenylgermyl)ethylketone (3a) and in molar ratio 1:6 to give l,l-diphenyl-3-(triphenylgermyl)propanol (4a).The compound 2a reacts with phenylmagnesium bromide in molar ratio 1:2 to give 3a and in molar ratio 1:3 to give 4a also.Dehydration of the compound 4a with dilute hydrochloric acid seems especially easy.Moreover,the compound la reacted with phenylmagnsium bromide in molar ratio 1:6,then the mixture was treated with dilute hydrochloric acid to give 1,1-diphenyl-3-(triphenylgermyl)-1-propene (5a) in one pot reaction.Alkyl Ge-C bond in the compound 5a can be cleaved selectively by lithium aluminium hydride ( LiAlH4) in good yiel  相似文献   

2.
Triazole derivatives are widely studied, because they represent the largest group of modern fungicides and are widely used both in human and veterinary therapy and in agriculture. We synthesized the title compound in which the thiophene ring was substituted by a 1,2,4-triazole group, a phenacyl group, a phenylaminol group and a benzene ring.  相似文献   

3.
We describe the synthesis of tert-butyl esters of 3-(2-hydroxybenzoyloxy)methyl-, 3-(dihydroxybenzoyloxy)methyl-, and 3-(diacetoxybenzoyloxy)methyl-7-chlorocephalosporanic acid sulfones by reaction of tert-butyl ester of 3-bromomethyl-7-chlorocephalosporanic acid sulfone with salts of hydroxy- and acetoxy-substituted benzoic acids. We have investigated the elastase-inhibiting properties of the compounds obtained and also their in vitro cytotoxic activity.  相似文献   

4.
Two new solvated benzohydrazone derivatives N′-(4-hydroxy-3-nitrobenzylidene)-3-methylbenzohydrazide-methanol-water (2/1/1) 2(C15H13N3O4)·CH3OH·H2O (1) and N′-(4-dimethylamino-benzylidene)-3-methylbenzohydrazide methanol monosolvate C17H19N3O·CH3OH (2) are prepared and characterized by elemental analysis, 1H and 13C NMR, and single crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic space group P21/c with unit cell dimensions a = 17.084(2) Å, b = 12.706(1) Å, c = 15.412(1) Å, β = 113.207(1)°, V = 3074.1(4) Å3, Z = 4, R 1 = 0.0567, and wR 2 = 0.1209. Compound 2 crystallizes in the monoclinic space group P21/n with unit cell dimensions a = 15.058(1) Å, b = 6.658(1) Å, c = 17.211(2) Å, β = 94.189(2)°, V = 1720.8(3) Å3, Z = 4, R 1 = 0.0611, and wR 2 = 0.1594. X-ray diffraction indicates that the asymmetric unit of 1 contains two independent benzohydrazone molecules, one methanol and one water molecules. The asymmetric unit of 2 contains one benzohydrazone molecule and one methanol molecule. Benzohydrazone molecules of the compounds display trans configurations with respect to the C=N double bonds. The crystal structures of the compounds are stabilized by hydrogen bonds and weak π...π interactions.  相似文献   

5.
An X-ray study of (3Z)-(±)-4-(2′-hydroxypropyl)amino-and (3Z)-4-(2′-hydroxyethyl)amino-pent-3-en-2-ones is reported. The bond lengths inside the H ring are equalized due to the classical N-H...O hydrogen bond between the carbonyl oxygen and the amino group. In the 4-(2′-hydroxyethyl)amino-pent-3-en-2-one crystal, due to the classical N-H...O bonds, infinite zigzag chains are formed along the 0b axis and arranged into a layered structure due to the weak C-H...O interactions. In (±)-4-(2′-hydroxypropyl)aminopent-3-en-2-one crystal, however, centrosymmetric dimers are formed, which are then linked by weak C-H...O intermolecular interactions to form a layered structure along the a0b plane.  相似文献   

6.
The reaction of 2-hydroxy-2-polyfluoroalkylchroman-4-ones with hydrazine affords 5-hydroxy-3-(2-hydroxyaryl)-5-polyfluoroalkyl-2-pyrazolines, whereas 2-polyfluoroalkylchromones under similar conditions produce 3(5)-(2-hydroxyaryl)-5(3)-polyfluoroalkylpyrazoles. 5-(2-Hydroxyaryl)-1-methyl-3-polyfluoroalkylpyrazoles were synthesized in the reaction with methylhydrazine, and the reaction with phenylhydrazine afforded regioisomeric 3(5)-(2-hydroxyphenyl)-1-phenyl-5(3)-polyfluoroalkylpyrazoles.  相似文献   

7.
The stereoselective syntheses of (Z)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c were investigated. The reaction of (3-carboethoxy-2-fu-ranyl)-methyltriphenylphosphonium bromide 1 with methyl 2-perfluoroalkynoates 2a-c in the presence of K2CO3 at room temperature gives two adducts, (E)-methyl 3-per-fluoroalkyl-4-( 3-carboethoxy-2-furanyl )-2-triphenylphosphoranylidene-3-butenoates 3a-c and (E)-methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-4-triphenylphos-phoranylidene-2-butenoates 4a-c. (Z)-Methyl 3-perfluoroalkyl-4-(3-carboethoxy-2-furanyl)-3-butenoates 5a-c can be synthesized stereoselectively with high yields when an aqueous DMF solution of 3c, 4c or a mixture of 3a-b and 4a-b was heated at 140℃ for 8 h.  相似文献   

8.
9.
TheantiPyrinldiazoaminoreagentsweresensitivefOrCd(II)andHg(II)11-3l-Receatly,anewreagrntlK4-antiPyrinl)-3<3-Chlorophenylytrime(APPT)wasSynthsized.ThecolourreahonofAnCPTwithmerCurywasstUdied-ThemethodfordeterminingmicroaznountofmempwithAPCPTwasmoresensitiveandhighlyselective.AnditwasusedtodeterIninemercmpcoboinnatUralwaterwithsatisfactryresults.ExperimeutalAPP~:Model75lspectrophotOmeter,ModelpH-2meter(madeinShanghai).Sbodard~solution:DissolveHgCl2(A.R.)inWate.AddseveraldroPso…  相似文献   

10.
Introduction In the preceding paper it was described that various 1-acyl-4-substituted thiosemicarbazides and their derivatives exhibited a broad spectrum of antibacterial activities. Kothari pointed out that some heterocycles linked with tetrazole and 1,2,4-triazole can be used as antiinflammatory agent. We have also demonstrated that both 3-(5-a- naphthyl)-2H-tetrazol-2-ylmethyl)-4-aryl-1,2,4-triazole-5-thiones and 3-(3-pyridyl)-  相似文献   

11.
Zhai HJ  Guo JC  Li SD  Wang LS 《Chemphyschem》2011,12(14):2549-2553
Anion photoelectron spectroscopy and theoretical calculations are combined to probe the structures and chemical bonding of two boron-rich oxide clusters, B(5)O(3)(-) and B(6)O(3)(-), which are shown to be appropriately formulated as B(2)(BO)(3)(-) and B(3)(BO)(3)(-), respectively. The anion clusters are found to each possess a bridging η(2)-BO group, as well as two terminal BO groups and are analogs of B(2)H(3)(-) and B(3)H(3)(-). This finding advances the boronyl chemistry and helps establish the isolobal analogy between boron-rich oxide clusters and boranes.  相似文献   

12.
Radiolysis kinetics in NO(3)(-) and NO(2)(-) solutions during γ-irradiation were studied at an absorbed dose rate of 2.1 Gy·s(-1) at room temperature. Air- or argon-saturated nitrate or nitrite solutions at pH 6.0 and 10.6 were irradiated, and the aqueous concentrations of molecular water decomposition products, H(2) and H(2)O(2), and the variation in the concentrations of NO(3)(-) and NO(2)(-) were measured as a function of irradiation time. The experimental data were compared with computer simulations using a comprehensive radiolysis kinetic model to aid in interpretation of the experimental results. The effect of nitrate and nitrite, present at concentrations below 10(-3) M, on water radiolysis processes occurs through reactions with the radical species generated by water radiolysis, (?)e(aq)(-), (?)O(2)(-), and (?)OH. The changes in H(2) and H(2)O(2) concentrations observed in the presence of nitrate and nitrite under a variety of conditions can be explained by a reduction in the radical concentrations. The kinetic analysis shows that the main loss pathway for H(2) is the reaction with (?)OH and the main loss pathways for H(2)O(2) are reactions with (?)e(aq)(-) and (?)OH. Nitrate and nitrite compete for the radicals leading to an increase in the concentrations of H(2) and H(2)O(2). Post-irradiation measurements of H(2), H(2)O(2), NO(2)(-) and NO(3)(-) concentrations can be used to calculate the radical concentrations and provide information on the redox conditions of the irradiated aqueous solutions.  相似文献   

13.
《Polyhedron》2004,23(2-3):273-282
Sodium salt of the fluorinated tris(pyrazolyl)borate ligand [HB(3-(CF3),5-(Ph)Pz)3] has been synthesized from the corresponding pyrazole and NaBH4 in high yield. It forms stable adducts with oxygen-based donors like THF and water. [HB(3-(CF3),5-(Ph)Pz)3]Na(THF) is monomeric in the solid state whereas {[HB(3-(CF3),5-(Ph)Pz)3]Na(H2O)}n forms a polymeric chain structure. These tris(pyrazolyl)boratosodium adducts show intra and/or inter-molecular sodium–fluorine interactions. X-ray crystal structures of [HB(3,5-(CF3)2Pz)3]Na(OEt2) and {[HB(3-(CF3),5-(CH3)Pz)3]Na(H2O)}2 also display similar CF⋯Na contacts. The copper carbon monoxide complex [HB(3-(CF3),5-(Ph)Pz)3]CuCO was prepared by treating [HB(3-(CF3),5-(Ph)Pz)3]Na(THF) with CuOTf in the presence of CO. The infra-red stretching frequency data show relatively high νCO value (2103 cm−1) indicating the presence of highly electrophilic copper site on [HB(3-(CF3),5-(Ph)Pz)3]CuCO. Crystal structure of 3-(CF3),5-(Ph)PzH is also reported. It forms “tub” shaped tetramers in the solid state.  相似文献   

14.
Methods for the preparation of 3-(α-nitroalkyl- and α-polynitroalkyl-ONN-azoxy)-4-nitraminofurazans with primary and secondary nitramine groups and their derivatives, including N,N′-bis[(3-(α-polynitromethyl-ONN-azoxy)furazan-4-yl]alkylen-N,N′-dinitramines, have been elaborated.  相似文献   

15.
16.
《European Polymer Journal》1986,22(4):293-298
Synthesis and optical resolution of 3-ethyl-3-phenylazetidinone-2 were improved to obtain (RS)-, (R)- and (S)-monomers having optical purities up to 98%, which could successfully be determined by 1H-NMR 250 MHz using tris[3-(2,2,2-trifluoro-l-hydroxymethylidene)d-camphorato]europium III as a shift reagent. These monomers were polymerized anionically in HMPT using potassium salt as a catalyst and by the addition of 1-acetyl-4,4-dimethylazetidinone-2 as a chain initiator. Optical purity of the starting monomer seemed to be maintained in the resulting polymers, the thermal properties of which were found to depend on the mean length of the stereoblocks contained in the chain. While the reactivity, in particular the case of polymerization, of monomer increased with the optical purity, no evidence could be obtained for stereoregulation by a preferential incorporation of a monomer enantiomer according to the configuration of the growing chain end unit.  相似文献   

17.
An X-ray study of [(μ-η23-HCCCH2)Cp2Mo2(CO)4]+(BF4) (1) and [(μ-η23-HCCCMe2)Cp2Mo2(CO)4]+(BF4) (2) reveals their structures to be similar to the structure of neutral compounds of the series (μ-η22-RCCR)Cp2Mo2(CO)4, the difference between 1 and 2 being mainly due to the markedly different MoC+ bond lengths, which accounts for different stability and fluxional behavior of these compounds in solution.  相似文献   

18.
由邻苯二甲酸酐为原料,经中间体3-羟基苯酞(3),再经溴丙烯及锡存在下3的烯丙基化、硼氢化氧化、铬酐氧化、二甲基锌甲基化,共6步反应合成了3-(3'-羟基丁基)异苯并呋喃-1(3H)-酮.  相似文献   

19.
1INThODUCT1ONInaprevi0uspaPer"',wereP0rtedthesyntheses0fsome1,3,4-diazaphospho-lidin-2-thione-4-oxidesandtheirhighselectiveherbicidalactivity.Althoughtherewereseveralreportsaboutthedesulphurisationofsomestraightchainthioureaderiva-tivest2'31,uptonow,thedesulphurisationreactionofcyclicthioureaderivativesutiliz-ingAgNO,-H,Osystemhasnotbeenstudied.InthispaPer,thedesulphurisation0fcis-3,4-diphenyl-5-(2,4-dichlorophenyl)-1,3,4-diazaphOSpholidin-2-thione-4-oasthecyclicsubstrateisrep0rtedfort…  相似文献   

20.
《Tetrahedron: Asymmetry》1999,10(19):3735-3745
A synthetic route to obtain (R)-(−) (1), (S)-(+)-3-(1-pyrrolyl)propyl-N-(3,5-dinitrobenzoyl)-α-phenylglycinate (2) and derivatives is described. In a first step, pyrrole derivatives were prepared using the Clauson-Kaas method. The esterification, second step, was performed using basic conditions due to sensitivity of the pyrrole group toward acidic conditions. A tautomeric equilibrium involving the stereogenic center induces the product epimerization. The substitution of DMAP and Et3N by a highly hindered base, proton-sponge®, furnished the final products without racemization. The ee of 1, 2 and of the corresponding methyl esters (3 and 4) were determined by 1H NMR analysis in the presence of optically active Eu(tfc)3. Epimerization was not observed in the preparation of the carboxylate salts (58).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号