一种苯并噻唑类稳定烯醇的合成及晶体结构

以2-甲基苯并噻唑和1,3-丙磺酸内酯为起始原料,合成了一种菁染料中间体2-(2-乙氧基-1-丁烯基)-1-(3-磺酸丙基)苯并噻唑(3).该染料中间体极易水解,对其水解产物(4e)采用红外光谱、核磁共振、质谱、元素分析和X射线单晶衍射分析等方法进行了表征.MS结果显示水解产物4e的分子量为327;在13C NMR谱图中,烯醇结构中与羟基相连的碳的化学位移为194.05,与之相连的另一个双键碳的化学位移为δ92.52;在IR谱图中,1618 cm-1处存在烯醇的特征吸收峰;通过X射线单晶衍射分析测定了水解产物的结构,进一步证实该水解产物是一种存在共轭芳基结构的稳定烯醇.     

新型异桥烯醇式双铜配合物的合成及磁交换作用的研究

合成了2个含不同外源桥基的双铜配合物[Cu_2(pfhmp)OH]·2H_2O和[Cu_2(pfhmp)N_3]·H_2O,pfhmp~(3-)表明N,N′-二异烟酰基-2-羧基-4-甲基-1,3-苯二甲醛双腙的脱氢阴离子。经元素分析、红外光谱、摩尔电导等手段推知两配合物均为异桥结构与烯醇式构型,变温磁化率测定表明改变外源桥基会明显改变2个铜离子之间的磁交换作用。     

烯醇式异桥双铜配合物的合成及磁交换作用的研究

合成了２个异桥双铜配合物：［Ｃｕ２（ｐｆｈｍｐ）Ｂｒ］·２Ｈ２Ｏ（１）和［Ｃｕ２（ｐｆｈｍｐ）Ｃ３Ｈ３Ｎ２］·２Ｈ２Ｏ（２），经元素分析、红外及摩尔电导等手段推知两配合物均为烯醇式构型。变温磁化率测定结果表明，由于外源桥的影响，铜离子间的反铁磁相互作用有明显差别。     

非呐酮的烯醇三甲基硅醚在紫外光照下的氟烷基化反应

本文报导了卤代氟烷与酮的烯醇硅醚的反应. 用3,3-二甲基-2-丁酮的烯醇三甲硅醚与等摩尔的1,1,1-三氟-2,2,2-三溴乙烷及催化量的过氧化月桂酰进行紫外光照, 得到二个馏份化合物: 第一馏份为Me3SiBr, 第二馏份含三个化合物, 分别是2,2-二甲基-5,5-二溴6,6,6-三氟-3-己酮, 1,1,1-三氟-2-溴-5,5-二甲基-2-烯-4-己酮和3,3-二甲基-2-丁酮. 上述化合物与NaHCO3或NaOH水溶液反应生成α,β-烯酮(Cl(CF2)n-1CF=CHCOCMe3), 得率好.     

贵州玉米螟性信息素的简易合成及田间生物活性测定初探

报道了亚洲玉米螟（ＯｓｔｒｉｎｉａＦｕｒｎａｃａｌｉｓＧｕｅｎｅｅ）性信息的素顺－１２－十四碳烯醇醋酸酯（Ａ）及其反应异构体（Ｂ）的立体选择性合成，以及它的田间生活活性测定试验，合成的关键步骤是通过控制羧基烯化反应体系的反应温度，用相应的ω－羟基季磷盐（Ｄ）和醛一步生成所需比例的（Ａ）（Ｂ）两个顺反式异构体混合物。     

四氟乙烯五聚体烯醇络合物及其溴化反应

碳原子数小于5的含氟烯醇三乙胺络合物,是一种亚稳态化合物,对它的研究已有不少报道。以四氟乙烯五聚体为原料的烯醇阴     

新型酮式,烯醇式双铜配合物的合成及磁交换作用研究

合成和表征了2个双核铜配合物——酮式-[CU_2(H_2L)Cl]Cl_2和烯醇式-[Cu_2(L)Cl]·H_2O,推知2个配合物分别为酮式和烯醇式,烯醇式配合物中铜离子间的反铁磁相互作用(J=-461.80cm~(-1))大于酮式配合物中的相应值(J=-33.16cm~(-1))。     

Acid Catalyzed Condensation of Phenylethanal Enol or Thiol Enol Ether to 2-Phenylnaphthalene

Treatment of enol ether or thiol enol ether of phenylethanals with sulfuric or polyphosphoric acid in toluene or xylene gave 2-phenylnaphthalene in good yield. More importantly, a one-pot reaction has been developed.     

毛细管柱-气相色谱法测定谷物中脱氧雪腐镰刀菌烯醇和雪腐镰刀菌烯醇含量

谷物样品经乙腈-水(84+16)溶液提取,离心后经自制中性氧化铝-活性炭-二氧化硅固相萃取柱净化,所得净化液经三甲基硅烷咪唑(TMSI)-N,O-双三甲基硅基乙酰胺(BSA)-三甲基氯硅烷(TMCS)(3+3+2)试剂衍生后,产物用RTX-5MS毛细管柱分离,用电子捕获检测器测定脱氧雪腐镰刀菌烯醇(DON)与雪腐镰刀菌烯醇(NIV)。DON和NIV的质量浓度在0.05～4.0mg.L-1之间与峰面积呈线性关系,方法的检出限(3S/N)为0.01mg.kg-1。方法用于小麦粉中DON、NIV的测定,DON和NIV的加标回收率分别在92.6%～96.6%和90.9%～94.1%之间,测定值的相对标准偏差(n=5)均小于6%。     

相似分析/质谱法鉴别二十种脂肪族双烯-1-醇及乙酸酯

本文报道了二十个脂肪族双烯-1-醇和乙酸酯EI-质谱的特征, 并提出了相似分析法鉴别这些共轭双烯、孤立双烯的双键位置及几何异构体的质谱。     

Synthesis of vicinal perfluoroalkyl enol ethers

A convenient preparation of vicinal perfluoroalkyl enol ethers, by the action of alcohols on 1-bromo-1-perfluoroalkylethylenes in the presence of potassium hydroxide, is described. Some aspects of their reactivity are reported.     

Molecular Diversity of Tonghaosu Analogues, Selective Oxidation of the exo-Cyclic Double Bond of Spiroacetal Enol Ethers and Diasteroselective Synthesis of Spiro-Pyranone

Two methods including NBS/AgNO₃ system and MCPBA oxidation have been developed for the selective oxidations of the exo‐cyclic double bond of spiroacetal enol ethers 2 with multi reactive sites into spiro‐pyanones 3 and 4 . In addition, possible mechanisms for these conversions are proposed.     

Synthesis of racemic nitramine, isonitramine and sibirine

Condensation of enol ether 6 with methyl vinyl ketone led easily to ketoaldehyde 7 whose cyclisation afforded the azaspiranic enone 8, a key intermediate for the synthesis of the title alkaloids.     

New synthesis of arcyriaflavin-A via silyl enol ether-mediated and Fischer indolisations

A new synthesis of the natural product arcyriaflavin-A is described. It was brought about through Diels-Alder cycloaddition and two indolisations based on silyl enol ether nucleophilic attack and Fischer processes.     

Synthesis of 3-substituted 2-cyclohexenones through umpoled functionalization

A new protocol to obtain 3-substituted 2-cyclohexenones, was developed by reversing the chemical reactivity of 2-cyclohexenone. One-pot synthesis of 3-substituted 2-cyclohexenones can be achieved by treatment of 3-phenylthiosilyl enol ether with a mixture of t-BuLi/HMPA that allows hydrogen-selective exchange in presence of reactive electrophiles such as aldehydes, ketones and alkyl halides. This affords the corresponding product in moderate overall yield, after silyl enol ether cleavage and concomitant thiophenol elimination initiated with TBAF.     

双环烯醚的合成及其性质的研究

由内酯2和Tebbe试剂反应合成了双环烯醚化合物5-苄氧基-2,8-二亚甲基-3,4,9,10-四氢-2H,8H-苯并[1,2-b; 3,4-b']二吡喃(3), 环烯醚在酸性条件下很容易水解和异构化, 在酸存在下外环烯醚3于10 min内转化为内环烯醚4, 较长的反应时间只能得到水解物或其它分解产物.     

Synthesis of enol and vinyl esters catalyzed by an iridium complex

Enol and vinyl esters were successfully synthesized by the use of an iridium complex as a catalyst. The reaction of carboxylic acids with terminal alkynes in the presence of catalytic amounts of [Ir(cod)Cl]₂ and Na₂CO₃ gave the corresponding 1-alkenyl esters. The addition of carboxylic acids to alkynes principally took place in the Markovnikov fashion. In addition, by the use of an Ir complex combined with NaOAc various vinyl esters were prepared through the transvinylation between carboxylic acids and vinyl acetate.     

Synthetic utility of bowl-shaped tris(2,6-diphenyl-benzyl)silyl glyoxylate as a stable glyoxylate: application to highly diastereoselective aldol reactions

A stable glyoxylate can be successfully applied to both syn- and anti-selective aldol reactions by using two different kinds of ordinary Lewis acids. Thus, treatment of bowl-shaped tris(2,6-diphenylbenzyl)silyl glyoxylate 1 with enol silyl ether under the influence of BF₃·OEt₂ gave syn-aldol product, while the use of TiCl₄ afforded anti-aldol product with >97% selectivity.     

片呐酮的烯醇三甲基硅醚在紫外光照下的氟烷基化反应

酮的烯醇硅醚的富电子碳碳双键易被亲电子基团进攻,生成取代酮类化合物。例如,在TiCl_4等Lewis酸的存在下,卤代烷与酮的烯醇三甲硅醚反应生成2-烷基取代酮。迄今为止,还没有卤代氟烷与酮的烯醇非醚反应研究的报道。我们将3,3-二甲基-2-丁酮的烯醇三甲硅醚与等摩尔的1,1,1-三氟-2,2,2-三溴乙烷及催化量的过氧化月桂酰进行光照3h后,б_F-10 ppm处出现一新峰,与CF_3CBr_3(2)的δ_F0 ppm处峰的面积比为2:3。继续光照,δ_F-