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1.
相转移催化法合成1-O-酰基-四-O-乙酰基-β-D-吡喃己糖   总被引:10,自引:0,他引:10  
以氯化三乙基苄基铵作为相转移催化剂, 用2, 3, 4, 6-四-O-乙酰基-β-D-溴代吡喃葡萄糖和2, 3, 4, 6-四-O-乙酰基-β-D-溴代吡喃半乳糖与羧酸反应, 合成了相应的1-O-酰基-2, 3, 4, 6-四-O-乙酰基-β-D-吡喃葡萄糖和半乳糖。通过解析这些化合物的^1H NMR和红外光谱, 确证其糖甙键构型为β。该相转移催化法具有反应条件温和, 后处理简单和立体选择性强等优点。  相似文献   

2.
异氰酸苯醇和N-[2-(4,6-二甲基)-嘧啶基]-羟胺(5)反应生成1-[2-(4,6-二甲基)-嘧啶基]-1-羟基-3-苯基脲(6)。化合物(6)在三乙胺存在下和氯甲酸乙醇反应生成2-[2-(4,6-二甲基)-嘧啶基]-4-苯基-1,2,4-噁二唑烷-3,5-二酮(1)。  相似文献   

3.
本文给出了一条较好的制备7,8-二氢-6,6-二甲基-7,8环氧-6氢-吡喃[2,3-f]苯并-2,1,3-噁二唑的合成路线,即由对乙酰氨基苯酚经酯化、Fries重排、环合、还原、脱水、硝化、脱酰基、氧化、脱氧和催化环氧化等反应制得标题化合物,其结构经元素分析和光谱数据确证。  相似文献   

4.
1,4 - Dimethyl - 2 - nitro - 3 - phenylsulphonylnaphthalene (2) reacts with sodium benzenethiolate in DMSO at 120° to give 1 - methyl - 2 - nitro - 4 - phenylthiomethylnaphthalene (4) [tele-substitution product (TSP) of the phenylsulphonyl group] and 1,4 - dimethyl - 3 - phenylsulphonyl - 2 - phenylthionaphthalene (5) [normal substitution product (NSP) of the nitro group]. The analogous reactions of 2 with sodium 2,4,6- trimethylbenzenethiolate and of 2,3 - bisphenylsulphonyl -1,4 - dimethylnaphthalene (3) with sodium benzenethiolate or aliphatic amines give only TSPs of the phenylsulphonyl group. In the case of the reaction of 2 with aliphatic amines both the possible TSPs (tele-substitution of the phenylsulphonyl or of the nitro group) were isolated in 9:1 relative yield. All the data show that the phenylsulphonyl is a leaving group far better than the nitro in such tele-substitution processes. The mechanism previously proposed to account for the formation of TSPs from 1,4-dimethyl - 2,3 - dinitronaphthalene is strongly supported by the obtained results.  相似文献   

5.
Summary Two 1,2,3-triazole anticonvulsants, 1-(4-methylsulfone-phenyl)-5-(4-fluoro-phenyl)-5-[14C]-1,2,3-triazole and 1-(4-sulfonamide-phenyl)-5-(4-fluoro-phenyl)-5-[14C]-1,2,3-triazole, both labeled with carbon-14 in the 5-position were prepared from para-fluoro-benzonitrile-[cyano-14C].  相似文献   

6.
以分级结晶和柱层析法对手性配体2-(2-吡啶基)-4-羧乙基-1,3-噻唑烷(A)进行了异构体分离提纯。将其与[Rh(COD)Cl]_2制备的原位催化剂用于催化苯乙酮及其它几种芳香酮的不对称硅氢化反应,化学收率达90%左右,光学纯度达80%e.e.左右,噻唑烷环上的C_2构型对催化反应结果无影响,C_4位上酯基的影响也不大。  相似文献   

7.
由苯并-15-冠-5经硝化、还原两步反应,制得4',5'-二氨基苯并-15-冠-5(2)。后者与水杨醛或其取代衍生物缩合,合成了一系列新的冠醚化双Schiff碱化合物1a~1h,经元素分析、IR、^1^HNMR和MS确证了其结构。  相似文献   

8.
Highly efficient and selective syntheses of the title compounds are described. The cornerstone of the synthetic plan is the tandem inter [4 + 2]/inter [3 + 2] cycloaddition process. These syntheses differ from previous applications of this strategy in that they incorporate an alkylation in the hydrogenolysis step to close the second ring of the azabicyclic systems. Notable features of the sequence are (1) the highly regio- and stereoselective [3 + 2] cycloaddition of nitronate 15 with siloxymethyl (Z)-beta-silylvinyl ketone (Z)-22b and (2) the highly selective reduction of the resulting ketone 24a with L-Selectride. A single-crystal X-ray structure analysis of synthetic (-)-7-epiaustraline confirmed that the targeted structure was successfully synthesized. This stimulated a reexamination of the structural assignment of the natural product. (-)-1-Epicastanospermine was synthesized in four steps from the common intermediate 27a. The absolute configuration of (-)-1-epicastanospermine was assured by single-crystal X-ray structure analysis of intermediate (-)-27a. Thus, the sign of the optical rotation had to be revised. The overall efficiency of these syntheses were 9 steps and 23% yield for (-)-7-epiaustraline and 10 steps and 20% yield for (-)-1-epicastanospermine  相似文献   

9.
报道了取代的邻羟基苯乙酮(1a~1e)经Vilsmeier-Haack反应一步制得3-醛基色酮(2a~2e),2a~2e与取代的芳酰肼(3a~3c)缩合制得15个酰腙类化合物(4a~4o),4a~4o在醋酸酐作用下关环得15个3-(2-苝二唑啉基)-色酮(5a~5o),并通过元素分析,IR,~1H NMR和MS诺数据确证了上述化合物的结构。  相似文献   

10.
(+/-)-1-[3-(2-Methoxyphenoxy)-2-hydroxypropyl]-4-[(2,6-dimethylphenyl)aminocarbonylmethyl]piperazine dihydrochloride salt was studied spectroscopically. Complete NMR assignments for dihydrochloride salt were made using DEPT, H-H COSY, as well as HMQC and HMBC heteronuclear correlation techniques.  相似文献   

11.
张自义  杨丰科 《有机化学》1994,14(5):553-557
本文首先用5-(3-吡啶)-2H-四唑乙酰基酰肼与芳酰基异硫氰酸盐反应制备成化合物1-[5-(3-吡啶)-2H-四唑乙酰基]-4-芳酰氨基硫脲化合物1a~j, 然后用冰醋酸回流处理1a~j得到一系列化合物5-[5-(3-吡啶)-2H-四唑亚甲基]-2-芳酰氨基-1,3,4-噻二唑2a~j . 化合物1a~b在强碱介质中首先发生降解, 然后进行环化反应 .  相似文献   

12.
用KBH_4,CaCl_2为还原剂使D及L缬氨酸甲酯还原得到光学活性产物R-3-甲基-2-氨基丁醇(2a)及S-3-甲基-2-氨基丁醇(2b)。2a,2b同CS_2在KOH存在下反应得到(R)-4-异丙基四氢噻唑-2-硫酮(3a)及(S)-4-异丙基四氢噻唑-2-硫酮(3b)。肉桂酰氯分别同3a及3b在Et_3N存在下反应得到N-肉桂酰(R)-4-异丙基四氢噻唑-2-硫酮(4a)及N-肉桂酰(S)-4-异丙基四氢噻唑-2-硫酮(4b)。用半经验的量子化学PM3方法研究了反应物和产物的电子结构,得到了产物的最优构型和电荷键序分布以及反应焓变。  相似文献   

13.
《Polyhedron》1987,6(5):1059-1064
The reactions of palladium(II) chloride with 1,4 - diphenyl - 2,3 - dimethyl - 1,4 - diazabutadiene and 1,4 - di(p - methoxyphenyl) - 2,3 - dimethyl - 1,4 - diazabutadiene are described. With 1,4 - diphenyl - 2,3 - dimethyl - 1,4 - diazabutadiene diimine fission is produced, giving rise to a product identified by elemental analysis, IR and Raman spectra, and X-ray diffraction, as trans-dichlorobis(aniline) palladium(II). The complex is soluble in dimethylformamide and crystallizes with two molecules of solvent. The substance crystallizes in the monoclinic space group P21/n. The X-ray data were refined to R = 0.047 and Rw = 0.046. Final distances are PdN = 2.060(5)Åand PdC1 = 2.299(2)Å. There are two bifurcated intermolecular NH ... C1 and CH... C1 hydrogen bonds which, together with one more intermolecular hydrogen bond NH... O, are responsible for the packing of the molecules. However, when 1,4 - di(p - methoxyphenyl) - 2,3 - dimethyl - 1,4 - diazabutadiene was treated with palladium chloride under the same conditions cis - dichloro - 1,4 - di(p - methoxyphenyl) - 2,3 - dimethyl - 1,4 - diazabutadiene was formed, as deduced from elemental analysis, and IR and Raman spectra.  相似文献   

14.
在DMF溶剂中,不外加催化剂使邻取代芳香醛(1)与5,5-二甲基-1,3-环己三酮(2)发生缩合和加成反应生成3,3,6,6-四甲基-4a-羟基-9-芳基-1,8二氧化-2,3,4,4a,5,6,7,8,9a-十氢化-1H氧杂蒽(3a~3d)。在同样条件下,邻羟基芳香醛与5,5-二甲基-1,3-环己三酮则发生缩合,加成和脱水反应生成3,3-二甲基-9-(5,5-二甲基-3-羟基-2-环己烯-1-酮-2-基)-1-氧代-2,3,4,9-四氢化-1 氧杂蒽(4a~4b)。用单晶X-射线分析法确定了产物3a和4a的晶体结构。  相似文献   

15.
用三苯基氢化锡,三对甲苯基氢化锡作为锡氢化试剂与9-乙炔基-9-芴醇进行反应,合成了2个有机锡化合物:[Z]-2-(三苯基锡基)-1-(9-芴醇)乙烯(1)和[Z]-2-(三对甲苯基锡基)-1-(9-芴醇)乙烯(2)。化合物1和2分别与ICl,Br~2,I~2反应,得到6个有机锡一卤化物,6个有机锡二卤化物和2个有机锡混合卤化物(3-16)。有机锡一碘化物7,13和有机锡二碘化物8,14与KOH乙醇溶液反应,分别得到相应的有机锡氢氧化物17,18和有机锡氧化物19,20。有机锡二碘化物8,14分别与含氮双齿配体1,10-邻菲罗啉(Phen),2,2'-联吡啶(Bipy),8-羟基喹啉(Oxin)反应,得到6个相应的配合物21-26。26个新化合物通过元素分析,锡含量测定,IR,^1HNMR测定对其结构进行了表征。同时测定了化合物2的晶体结构,晶体属单斜晶系,空间群P2~1/c。化合物2是以Sn原子为中心扭曲的四面体构型。  相似文献   

16.
微波作用下2-烃基-4-喹啉酮的简便合成法   总被引:14,自引:0,他引:14  
在微波作用下5-(甲硫亚烃基)丙二酸亚异丙酯可与芳胺发生加成消除反应,首先生成5-(芳胺基亚烃基)丙二酸亚异丙酯,继而进一步闭环,提供了2-烃基-4-喹啉酮的快速合成法。  相似文献   

17.
2-(Tributylstannoxy)-, 2(triphenylstannoxy)- and 2-(trimethylsiloxy)-3- hydro-4-alkyl- or -4-phenyl-1,3,5,2-oxadiazaboroles have been synthesized, and their properties examined.  相似文献   

18.
Several 3- [ 1- (4-ethoxyphenyl)-5-methyl- 1,2, 3-triazol-4-yl ]-6-substituted-s-triazolo [ 3,4- b ]- 1,3,4-thiadia zoles have been synthesized and the structures of these compounds were established by MS, IR and 1H NMR spectral data.  相似文献   

19.
Structure of an alkaline hydrolysis product of heavenly blue anthocyanin was determined to be trans-4-0-(6-0-(trans-3-0-(β-D-glucopyranosyl)caffeyl)-β-D- glucopyranosyl)caffeic acid (1).  相似文献   

20.
曾和平 《有机化学》2000,20(1):94-97
为了发展转变点温度(Tc)高的有机磁性分子,设计合成了4,5-四硫富瓦烯-双(2,3,6,7-二苯基-氮杂环庚烷-1-氧化物)。反应混合物均经硅胶柱和设备HPLC分离和纯化,产物的结构由MS、^1^HNMR、^1^3CNMR等确定。  相似文献   

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