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1.
在吡咯或吲哚自身N-H的催化下,在无溶剂条件下合成了3个吡咯和5个吲哚Michael加成产物(2a~2c和3a~3e,其中2b和3a~3e为新化合物),收率80%~92%, 3a~3c的d/r值分别为3.8 : 1, 1.3 : 1和1.1 :1,其结构经1H NMR, 13C NMR, IR和HR-MS(ESI)表征。  相似文献   

2.
雷英杰  丁玫  姚庆佳 《合成化学》2017,25(5):384-388
以邻氨基苯酚(1)和芳醛(2a~2i)[或脂肪醛(2j, 2k)]为原料,聚乙二醇(PEG-400)为溶剂,稻壳灰负载氯磺酸(AC)为固体酸催化剂,采用超声辅助的“一锅法”合成了11个2-取代苯并噁唑(3a~3k),其结构经1H NMR, IR和元素分析确证。以3a和3j的合成为例,优化了反应条件。结果表明:在最优合成条件[1 1 mmol, 2 1.2 mmol, AC 10 mol%, PEG-400 5 mL,于200 W超声30 min(3a)或60 min(3j)]下,3a和3j收率分别为92.4%和82.4%。 AC重复使用5次,3a收率84.7%。 PEG-400回收率约79%。  相似文献   

3.
Smog chamber/FTIR techniques were used to study the atmospheric chemistry of 3-pentanol and determine rate constants of k(Cl+3-pentanol) = (2.03 +/- 0.23) x 10 (-10) and k(OH+3-pentanol) = (1.32 +/- 0.15) x 10 (-11) cm (3) molecule (-1) s (-1) in 700 Torr of N 2/O 2 diluent at 296 +/- 2 K. The primary products of the Cl atom initiated oxidation of 3-pentanol in the absence of NO were (with molar yields) 3-pentanone (26 +/- 2%), propionaldehyde (12 +/- 2%), acetaldehyde (13 +/- 2%) and formaldehyde (2 +/- 1%). The primary products of the Cl atom initiated oxidation of 3-pentanol in the presence of NO were (with molar yields) 3-pentanone (51 +/- 4%), propionaldehyde (39 +/- 2%), acetaldehyde (44 +/- 4%) and formaldehyde (4 +/- 1%). The primary products of the OH radical initiated oxidation of 3-pentanol in the presence of NO were (with molar yields) 3-pentanone (58 +/- 3%), propionaldehyde (28 +/- 2%), and acetaldehyde (37 +/- 2%). In all cases the product yields were independent of oxygen concentration over the partial pressure range 10-700 Torr. The reactions of Cl atoms and OH radicals with 3-pentanol proceed 26 +/- 2 and 58 +/- 3%, respectively, via attack on the 3-position to give an alpha-hydroxyalkyl radical, which reacts with O 2 to give 3-pentanone. The results are discussed with respect to the literature data and atmospheric chemistry of 3-pentanol.  相似文献   

4.
吴小云  尹晓刚  龚维  王野  陈卓 《合成化学》2016,(11):959-962
以蒙脱土负载碘(MMT/I2)作催化剂,醛(1a~1g)与吲哚(2)反应合成双吲哚甲烷衍生物(3a~3g),其结构经1H NMR和IR确证。以3a的合成为例,研究了催化剂、溶剂、反应时间、温度和物料比r[n(1)∶n(2)]对3产率的影响。结果表明:在最佳合成条件(2 1 mmol,r=1.1∶2.0,10 mol%MMT/I2,乙腈1 m L,于25℃反应5min)下,3a~3g产率67.9%~96.2%。MMT/I2循环使用3次,3a产率78.6%。  相似文献   

5.
Three new triterpenoid saponins, gypsosaponins A-C (1-3), were isolated from the roots of Gypsophila oldhamiana (Caryophyllaceae). Their structures were established as 3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta-D-glucuronopyranosyl quillaic acid 28-O-alpha-L-arabinopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside (1), 3-O-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-methyl-beta-D-glucuronopyranosyl gypsogenin 28-O-beta-D-glucopyranosyl-(1-->3)-[beta-D-xylopyranosyl-(1-->4)]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-fucopyranoside (2), and 23-O-beta-D-glucopyranosyl gypsogenic acid 28-O-beta-D-glucopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->6)]-beta-D-glucopyranoside (3), on the basis of various spectroscopic analyses and chemical degradations. The biological activities of 1-3 were examined inhibitory activity against pancreatic lipase, which showed inhibition of 58.2%, 99.2% and 50.3% at concentration of 1 mg/ml, respectively.  相似文献   

6.
于海丰 《应用化学》2009,26(6):667-670
在常温1-(1, 3-二噻-2-亚基)丙酮1f是无气味的、稳定的白色固体,它易通过易制备的3-(1, 3-二噻-2亚基)-2, 4-戊二酮1b的酸性条件下的脱乙酰化反应制得,产率为86%。在MeCOCl/MeOH体系中,在常温和回流条件下,1f能作为有效的1, 3-丙二硫醇替代试剂与醛和酮进行缩硫醛/酮化反应,高产率(86-99%)合成1, 3-二噻烷衍生物。与已报道的硫醇替代试剂1a-e相比,在缩硫醛/酮化反应中1f是活性最好的1, 3-丙二硫醇替代试剂。  相似文献   

7.
Five-coordinate and six-coordinate 2-methyl-2-propanethiolato complexes of zirconium, [Li(DME)(3)][Zr(SCMe(3))(5)] (1) and [(THF)Li](2)Zr(SCMe(3))(6) (2), were obtained from the ZrCl(4)/LiSCMe(3) reaction system. The control of the Zr coordination number, by the ether ligands, THF or DME, bound to Li, is demonstrated by the conversion of 2 into 1 upon dissolution in DME. 1 and 2 were crystallographically characterized. The structures are extensively disordered. Crystal data follow: 1, hexagonal P6(3)/m, a = b = 12.496(3) ?, c = 17.561(9) ?, Z = 2, V = 2375(1) ?(3), R = 5.0%, R(w) = 6.8%; 2, trigonal R32, a = b = 11.813(3) ?, c = 28.37(1) ?, Z = 3, V = 3428(1) ?(3), R = 5.2%, R(w) = 6.4%.  相似文献   

8.
The products of bromo and chlorofluorination of E and Z-1,2-dichloroethylenes, 1, 3-dichloro-1-propenes, 1, 1-dichloro- ethylene and 1, 3-dichloro-2-fluoro-1-propene by N-bromosuccinimide and hexachloromelamine in anhydrous hydrogen fluoride have been studied. It was found that the reaction was in all cases 100% regio and 93–100% trans-stereospecific with the exception of E-1, 2-dichloro-ethylene, its trans-stereospecificity being 85%.Threo and erithro-1-bromo-1, 2-dichloro-2-fluoroethanes, 2-bromo-1, 3-dichloro-1-fluoropropanes and 1, 2, 3-trichloro-1-fluoro-propanes as well 1, 1, 2-trichloro-2-fluoroethane, 1-bromo-2, 2-dichloro-2-fluoroethane, 1, 2, 2-trichloro-2 fluoroethane, 1-bromo-1, 3-dichloro-2, 2-difluoropropane, and 1, 1, 3-trichloro-2,2-difluoropropane were obtained in 50–70% yield.The bromination of E and Z-1, 3-dichloro-1-propenes with molecular bromine in carbon tetrachloride in the dark is non-stereospecific and gives a mixture of erithro and threo-1, 2-dibromo-1, 3-dichloropropanes in the ratio about 1:1. However, the bromination reaction in anhydrous hydrogen fluoride solution proceeds with a high degree of stereospecificity (94–95%) and gives threo-1, 2-dibromo-1, 3-dichloropropane from Z and erithro-1, 2-dibromo-1, 3-dichloropropane from E-1, 3-dichloro-1-propene.The data obtained are considered in terms of an electrophilic mechanism of halogenoalkene halogenation in anhydrous hydrogen fluoride and a free-radical mechanism in carbon tetrachloride.  相似文献   

9.
2-取代氨基-5-吡唑基-1,3,4-噁二唑的合成及生物活性   总被引:20,自引:3,他引:17  
取代氨基吡唑基噁二唑;2-取代氨基-5-吡唑基-1;3;4-噁二唑的合成及生物活性  相似文献   

10.
在乙酰乙酸乙酯和氧化亚铜共同催化下, 二-(1,3-二硫环戊烯-2-硫酮-4,5-二硫)合锌酸四乙基铵盐分别与2-碘吡啶(1a)、 3-碘吡啶(1b)和4-碘吡啶(1c)反应, 制得硫酮化合物2,3-二(2-吡啶硫基)-1,3-二硫环戊烯-2-硫酮(2a)、 2,3-二(3-吡啶硫基)-1,3-二硫环戊烯-2-硫酮(2b)和2,3-二(4-吡啶硫基)-1,3-二硫环戊烯-2-硫酮(2c). 在醋酸汞催化下, 硫酮化合物2a, 2b和2c分别被氧化为2,3-二(2-吡啶硫基)-1,3-二硫环戊烯-2-酮(3a)、 2,3-二(3-吡啶硫基)-1,3-二硫环戊烯-2-酮(3b)和2,3-二(4-吡啶硫基)-1,3-二硫环戊烯-2-酮(3c). 以亚磷酸三乙酯为偶联剂, 氧酮化合物3a, 3b和3c分别发生自偶联反应生成2,3,6,7-四(2-吡啶硫基)四硫富瓦烯(4a)、 2,3,6,7-四(3-吡啶硫基)四硫富瓦烯(4b)和2,3,6,7-四(4-吡啶硫基)四硫富瓦烯(4c). 采用核磁共振波谱(NMR)、 傅里叶变换红外光谱(FTIR)和质谱(MS)分析了所合成化合物的结构和组成, 通过X射线衍射分析确认了吡啶基四硫富瓦烯衍生物4b和4c的晶体结构. 循环伏安法研究结果表明, 化合物4a, 4b和4c呈现准可逆的两电子转移过程, 结合量子化学计算, 分析了不同位置取代的吡啶基对四硫富瓦烯电化学电势的影响.  相似文献   

11.
[reaction: see text] Treatment of 1,2-bis(ethynyl)benzene (1) with aqueous HX (X = Br, I) in hot 3-pentanone (100-105 degrees C, 2 h) afforded 1,2-bis(1'-haloethenyl)benzene species 2-Br and 2-I in 98% and 95% yields, respectively. The hydrochlorination of endiyne 1 failed to proceed at elevated temperature but was implemented efficiently by PtCl2 (5 mol %) in hot 3-pentanone (100 degrees C, 2 h) to give 1,2-bis(1'-chloroethenyl)benzene 2-Cl in 80% yield. In the presence of PtCl2 (5 mol %), these halides 2-Cl,2-Br, and 2-I were subsequently converted to 1-halonaphthalenes 3-Cl, 3-Br, and 3-I in the mother solution via sequential 6-pi electrocyclization and dehalogenation reactions. PtCl2 (5 mol %) also effected direct haloaromatization of endiyne 1 with HX (X = Cl, Br, I) and gave 1-halonaphthalenes 3-Cl, 3-Br, and 3-I in 64-71% yields. This investigation reports the scope and the regioselectivity of haloaromatization of various enediynes catalyzed by PtCl2.  相似文献   

12.
Visible light-harvesting cyclometalated Ir(iii) complexes with 3-(2-benzothiazoly)-7-diethylaminocoumarin as the C^N cyclometalation ligands were prepared. The ancillary N^N ligand is either 6-piperidine naphthalimide-phenanthroline (Ir-1) or 9-aminophenanthroline (Ir-3). Ir(ppy)(2)(Phen) was prepared as model complex (Ir-2). Ir-1 and Ir-3 show strong absorption of visible light (ε = 109?000 M(-1) cm(-1) or 112?000 M(-1) cm(-1) at 486 or 484 nm, respectively). All the complexes show room temperature phosphorescence with drastically different phosphorescence quantum yields (Φ(P) = 4.3%, 44.3% and 46.0% for Ir-1, Ir-2 and Ir-3, respectively). With steady state and time-resolved spectra, as well as DFT calculations, the T(1) excited states of Ir-1 and Ir-3 were proposed to be the (3)IL state, whereas the (3)MLCT state was proposed for Ir-2. Long-lived emissive triplet excited states (7.6 μs and 54.5 μs) were observed for Ir-1 and Ir-3, compared to the short T(1) excited state lifetime of Ir-2 (1.2 μs). The complexes were used as triplet photosensitizers for triplet-triplet annihilation upconversion and upconversion quantum yields (Φ(UC)) of 19.3% and 12.7% were observed for Ir-1 and Ir-3, respectively. No upconversion was observed for Ir-2 under the same experimental conditions.  相似文献   

13.
本文通过η^5-Bz~5C~5MNa与氧化偶联试剂Fe~2(SO~4)~3/HOAC/H~2O的反应合成了含η^5-五苄基环戊二烯基配体的两个金属-金属单键化合物[η^5-Bz~5C~5(CO)~3M]~2 (1: M=Mo; 2: M=W) , 产率分别为45%和19% . 1 在沸腾的甲苯中可进一步脱碳而以98%的产率生成金属-金属叁键化合物[η^5-Bz~5C~5(CO)~2Mo]~2 (3).1~3的结构均经碳氢分析, IR, ^1H NMR 和MS鉴定. 3的结构尚被单晶X射线衍射分析确证 .  相似文献   

14.
Dangel BD  Polt R 《Organic letters》2000,2(19):3003-3006
Me(2)Zn and Et(2)Zn added to aromatic and aliphatic aldehydes in the presence of 3 mol % of 2. (S)-1-Phenylethanol (91% ee) and (S)-1-phenylpropanol (86% ee) were synthesized from benzaldehyde and (S)-1-furan-2-yl-1-propanol (86% ee) from 2-furaldehyde. Nonanal and 3-phenylpropanal provided (S)-3-undecanol (96% ee) and (S)-1-phenyl-3-pentanol (94% ee). A solid-phase variant was effective with reduced ee's (e.g., 86% ee --> 79% ee) for (S)-1-phenylpropanol.  相似文献   

15.
新型3,5-二芳基吡唑衍生物的合成与抑菌活性   总被引:1,自引:1,他引:1  
以2-氯苯甲醛与2,4-二氯苯乙酮缩合形成α,β不饱和酮,然后和水合肼关环形成3-(2,4-二氯苯基)-5-(2-氯苯基)吡唑结构骨架,合成了8个未见文献报道的3-(2,4-二氯苯基)-5-(2-氯苯基)-4,5二氢-N-酰基吡唑类衍生物。经过元素分析、红外光谱、核磁共振氢谱测试技术对其结构进行了表征。对新合成的化合物进行了初步生物活性测试结果表明,在化合物的质量浓度为50 mg/L时,化合物3f对水稻纹枯菌和稻瘟病菌的抑菌率分别为55.2%和57.1%。化合物3g对水稻纹枯菌、稻瘟病菌和油菜菌核菌的抑菌率分别为52.3%、60.0%和50.4%。  相似文献   

16.
以K_2CO_3为碱,β-酮酸酯与2-苯二甲酰亚氨基丙烯酸甲酯经共轭加成反应合成了一系列α-氨基酸衍生物,收率88%~99%,d/r值1.2∶1~1.3∶1,其结构经1H NMR,13C NMR和HR-MS(ESI-TOF)确证。  相似文献   

17.
With K-band EPR (Electron Paramagnetic Resonance), ENDOR (Electron-Nuclear DOuble Resonance), and EIE (ENDOR-induced EPR) techniques, three free radicals (RI-RIII) in L-lysine hydrochloride dihydrate single crystals X-irradiated at 298 K were detected at 298 K, and six radicals (R1, R1', R2-R5) were detected if the temperature was lowered to 66 K from 298 K. R1 and RI dominated the central portion of the EPR at 66 and 298 K, respectively, and were identified as main chain deamination radicals, (-)OOC?H(CH(2))(4)(NH(3))(+). R1' was identified as a main chain deamination radical with the different configuration from R1 at 66 K, and it probably formed during cooling the temperature from 298 to 66 K. The configurations of R1, R1', and RI were analyzed with their coupling tensors. R2 and R3 each contain one α- and four β-proton couplings and have very similar EIEs at three crystallographic axes. The two-layer ONIOM calculations (at B3LYP/6-31G(d,p):PM3) support that R2 and R3 are from different radicals: dehydrogenation at C4, (-)OOCCH(NH(3))(+)CH(2)?H(CH(2))(2)(NH(3))(+), and dehydrogenation at C5, (-)OOCCH(NH(3))(+)(CH(2))(2)?HCH(2)(NH(3))(+), respectively. The comparisons of the coupling tensors indicated that R2 (66 K) is the same radical as RII (298 K), and R3 is the same as RIII. Thus, RII and RIII also are the radicals of C4 and C5 dehydrogenation. R4 and R5 are minority radicals and were observed only when temperature was lowered to 66 K. R4 and R5 were only tentatively assigned as the side chain deamination radical, (-)OOCCH (NH(3))(+)(CH(2))(3)?H(2), and the radical dehydrogenation at C3, (-)OOCCH(NH(3))(+)?H(CH(2))(3)(NH(3))(+), respectively, although the evidence was indirect. From simulation of the EPR (B//a, 66 K), the concentrations of R1, R1', and R2-R5 were estimated as: R1, 50%; R1', 11%; R2, 14%; R3, 16%; R4, 6%; R5, 3%.  相似文献   

18.
研究了水溶性钌-氢配合物RuHCl(TPPTS)3在水/有机两相体系中催化1-己烯双键异构化反应.考察了反应温度、时间、膦配体浓度、相转移催化剂CTAB浓度以及底物与催化剂摩尔比等对转化率和产物选择性的影响.在最佳条件下1-己烯转化率达到82.4%,2-己烯选择性21.2%,3-己烯61.2%,没有发现骨架异构化.催化剂可重复使用5次.  相似文献   

19.
N-tert-Butyloxycarbonyl- and N-benzenesulfonyl-beta-hydroxyvalines 1a and 1b were, respectively, synthesized in enantiomerically pure form by a two-step protocol from their enantiomeric N-protected serine methyl esters 2a and 2b. The addition of CH(3)MgBr to 2a and 2b provided diols 3a and 3b, respectively as major products in 83% and 81% yields. Selective oxidation of diols 3a and 3b was performed using a TEMPO, NaClO(2), NaOCl cocktail in 96% and 93% respective yields. This two-step process effectively furnished multigram amounts of enantiopure N-Boc-beta-hydroxyvaline 1a.  相似文献   

20.
建立了一种超高效合相色谱法( Ultra performance convergence chromatography,UPC2)分离和测定盐酸兰地洛尔中立体异构体的方法。本方法选用Daicel CHIRALPAK? IF手性色谱柱(150 mm ×4.6 mm,3μm),以CO2为流动相,甲醇-正丁醇-乙腈(1:1:1, V/V)+0.5%氨水为助溶剂,梯度洗脱,流速为2.8 mL/min,检测波长为223 nm。在建立的UPC2条件下,盐酸兰地洛尔的R,R-异构体、R,S-异构体和S,R-异构体的检出限分别为0.3、0.4和0.3 mg/L;线性范围分别为2~300 mg/L、5~300 mg/L和2~300 mg/L;加标回收率分别为103.4%,91.8%和101.7%;进样精密度分别为0.06%,0.09%和0.08%(n=6)。本方法能够满足盐酸兰地洛尔样品中3个立体异构体检查的相关要求。  相似文献   

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