Studies on New Additions to 5-Methoxy-2 (5H)-Furanone: 1, 4-Addition of Grignard Reagents, and 1,3-Dipolar Cycloaddition of Silyl Nitronates

1,4-Addition reaction of Grignard's reagent to 5-methoxy-2(5H)-furanone 1 was accomplished. which provided a new possible route for synthesizing beta -alkyl-Y-alkyloxy-Y-butyrolactone. A novel concise method of preparing fused heterocyclic compounds was offered by 1,3-dipolar cycloaddition reaction of silyl nitronates to 1.

POLYMER-SUPPORTED GRIGNARD REAGENT AND ITS USE IN THE FUNCTIONALIZATION OF POLYMER

Polymeric Grignard Reagent (PGR) based on the chloromethylated poly(ST-co-DVB) resinhas been prepared by means of anthracene-magnesium complex in THF (Anth-Mg-THF), andpolymer matrix with long polymethylene spacer was synthesized via the coupling reaction betweenPGR and α, ω-dibromoalkanes. Based on the studies of factors affecting the coupling, such ascatalyst,reaction time,the length of spacer etc.,this paper offers the optimal reaction conditionsand three typical experiment procedures. The mechanism for the formation and coupling reactionof PGR are also discussed.

Synthesis of C-Glucosides from Grignard Reagents Prepared by Activated Magnesium

l-α-biaomo-2,3,4,6-tetra-O-acetyl-D-giucopyranose reacts with Grignard eagents prepared frorn the acnvated magnesium under very mild condition to ellord C- glucosides in a very high yield compared with Grignard Reagent prepared from usual method.β-anomer predominates in the reaction, mixture The configuration of anomers was assigned by 13C NMR spectra.

Studies on Silicon-Containing Fragrance Raw Materials( Ⅲ )——The Addition of 5-Trimethylsilylcyclohex-3-enone with Grignard Reagent

The present paper narrates the addition of 5-trimethylsilylcyclohex-3-enone to Grig-nard reagent to give 1-substituted 5-trimethylsilylcyclohex-3-enol in a good yield. The stereochemistry of the addition reaction and their products are discussed.

Reaction of Polymer-supported Selenovinyl Bromide with Grignard Reagents: A Facile Route to the Synthesis of (E)-1, 2-Disubstituted Olefins

Polymer-supported selenovinyl bromide, easily prepared from polymer-supported selenenyl bromide with acetylene, reacts with different Grignard reagents using a step-by-step strategy to obtain （E）-1, 2-disubstituted ethenes in good yields.

(Z)-a-Selanyl Alkenyl Grignard Reagents as Convenient Precursors for Stereoselective Synthesis of Trisubstituted Alkenes

Z)-a-Selanyl alkenyl Grignard reagents 2 were prepared conveniently by treatment of a-bromovinylselenides 1 with magnesium filings in THF. Intermediates 2 were reacted with alkyl iodides in the presence of CuI or Pd(PPh3)4 to afford (Z)-1,2-disubstituted vinylselenides 3, which were cross-coupled with Grignard reagents in the presence of (PPh3)2NiCl2 to give trisubstituted alkenes 4 stereoselectively in good yields.

Synthesis of Symmetric Diketones from Imidazolinium Salt and Bis-Grignard Reagents

The reaction of 2-substituted imidazolinium salt with bis-Grignard reagents is reported and a new method for the synthesis of symmetric diketones from carboxylic acids and bis-Grignard reagents is provided.

Synthesis of Large-ring Cycloalkanediones from Bis-Grignard Reagent and Dinitriles

Cyclododecanedione and 1, 8-cyclotetradecanedione were prepared from bis-Grig- nard reagent and dinitriles. This is a convenient synthetic method for large-ring cycloalkanediones.

α-羰基烯酮环二硫代缩醛化学(Ⅹ)——β,β-1,5-亚丙二硫基-α,β-不饱和酮与烯丙基Grignard试剂加成物的酸催化反应取向研究

β,β-1,5-亚丙二硫基-α,β-不饱和酮2b和2-甲基烯丙基氯化镁加成可得醇3b.在BF_3·Et_2O催化下,3b经分子内环合芳构化生成芳硫醚5b.2和烯丙基溴化镁反应得醇4,4在BF_3·Et_2O催化下经β-消除脱水生成共轭多烯类化合物6.二硫缩醛基以环和非环结构及环的大小对2与烯丙基Grignard试剂加成物在酸催化下的反应取向有重要影响.

α-羰基烯酮环二硫代缩醛化学(Ⅵ)——β,β-1,3-亚丙二硫基-α,β-不饱和芳酮与烯丙基Grignard试剂加成物脱水反应的研究

提出了由β,β-1,3-亚丙二硫基-α,β-不饱和芳酮类化合物(1)与苄基氯化镁及烯丙基溴化镁加成所得的醇(2)在BF_3·Et_2O催化下脱水生成共轭烯烃(3)新的合成途径,合成了13种新化合物,结构经~1H N-MR、IR、UV及元素分析等确证.并对这一新合成途径的反应机制进行了讨论.

Grignard试剂同6，6－二烷基富烯反应的研究

烯丙基卤化镁和环戊二烯基溴化镁同６，６－二烷基富烯分别进行富烯环外双键的加成和还原反应，生成的取代环戊二烯基负离子用（ＣｐＴｉＣｌ＿２）＿２Ｏ（Ｃｐ＝环戊二烯基）或ＴｉＣｌ４配合，合成通式为Ｃｐ（Ｃ＿５Ｈ＿１－ＣＲＲ￣１－ＣＨ＿２ＣＨ＝ＣＨ＿２）ＴｉＣｌ＿２和（Ｃ＿５Ｈ＿４ＣＨＲＲ￣１）＿２ＴｉＣｌ＿２的化合物。对烯丙基卤化镁、环戊二烯基溴化镁同富烯的反应机理进行了探讨。

对甲基苯甲醛的Grignard试剂合成法

醛类化合物尤其在香料工业中使用相当广泛. 但由于其容易氧化和聚合,合成难度大,产率低[1]. 对甲基苯甲醛是允许使用的食用香料之一,主要用于果仁香精,它还是合成纤维、医药、染料、增白剂的中间体,市场需求量大[2]. 其合成方法很多,其中值得注意的是Grignard试剂法[3],其合成温度不高. 本文用Grignard试剂p-CH3C6H4MgBr与1,3-二甲基苯并咪唑盐加成-水解生成对甲基苯甲醛,其合成温度也不高,合成路线如下:

α－羰基烯酮环二硫代缩醛化学（ⅩⅤ）──β，β－1，3－亚丙二硫基－α，β－不饱和芳酮与2－甲基烯丙基Grignard试剂加成物的酸催化取代－环合芳构化反应

α－羰基烯酮环二硫代缩醛化学（ⅩⅤ）──β，β－１，３－亚丙二硫基－α，β－不饱和芳酮与２－甲基烯丙基Ｇｒｉｇｎａｒｄ试剂加成物的酸催化取代－环合芳构化反应杨智蕴，王子苓，刘群，胡玉兰（东北师范大学化学系，长春，１３００２４）关键词β，β－１，３－亚...

Remediation of in-situ Leach Mining Contaminated Soil by Amendment-plant Synergism

This study aimed to remediate in-situ leach mining contaminated soil by amendment-plant synergism. The results showed that plant species exhibited ex-tremely significant effects on the concentration of nitrate nitrogen; to be specific, the concentration of nitrate nitrogen in soil planted with wheat was reduced from 692.19 mg/kg to lower than 100 mg/kg; when the mass ratio of amendment to soil reached 3：50 and the amendment particle size was 1-2 mm, the concentration of nitrate ni-trogen in soil planted with wheat was reduced to 43 mg/kg. The amendment type exhibited extremely significant effects on the concentration of ammonium nitrogen; to be specific, when the mass ratio of amendment to soil reached 10：50, the concen-tration of ammonium nitrogen in soil added with 2-3 mm zeolite was reduced from 23 593.75 to 3 300 mg/kg on day 15. Amendments and plants mainly exhibited desorption performance for sulfate radical in soil, and the amendment type extreme-ly significantly affected the concentration of sulfate radical; to be specific, the con-centration of sulfate radical in soil added with limestone increased from 370 mg/kg to 900 mg/kg on day 7.

用Grignard试剂C_6H_5MgBr合成苯甲醛

Benzaldehyde was prepared from the addition hydrolysis reaction of C 6H 5MgBr with 1,3 dimethylbenzimidazolium iodide.The reaction mechanism is suggested and discussed.

利用Grignard试剂的甲酰化反应合成对甲氧基苯甲醛

Methoxybenzaldehyde is prepared from the addition-hydrolysis reaction of p-CH 3OC 6H 4MgBr with 1,3-disubstituted benzimidazolium salt. The reaction mechanism is discussed. 1,3-Dialkyl has little influence on the yield.

α-羰基烯酮环二硫代缩醛化学(XXXVI)──β,β-1,3-亚丙二流基-α,β-不饱和芳酮与Grignard试剂加成物的硅胶催化分解反应

以β，β-1，3-亚丙二硫基-α，β-不饱和芳酮2与烯丙基或等基Grfenard试剂可选择性地进行1，2-加成得醇3、4，在硅胶G的催化下，醇3、4可分解生成β，γ-不饱和芳酮5、6．并对该分解反应的机制进行了初步探讨．

新型磷配体的设计合成及与钯配合催化氯代芳烃与Grignard试剂偶联反应的应用

设计合成了1,2-二(P,P-二苯基磷基)环己烯配体和二金刚烷基苄基磷配体,将这两种新配体与钯配合催化氯代芳烃与氯代芳烃Grignard试剂的偶联反应。1,2-二(P,P-二苯基磷基)环己烯配体在0.1%mol的催化用量时催化收率达95%。

α-肉桂酰基二硫缩烯酮与Grignard试剂的加成反应区域选择性研究——烷硫基对反应的调控作用

乙基、苯基卤化镁等Grignard试剂与具有三亲电中心的α 肉桂酰基二硫代缩烯酮类化合物 1反应 ,当 1中的烷硫基为二乙硫基、1,3 亚丙二硫基、1,4 亚丁二硫基时 ,Grignard试剂加成到与芳烃相连的碳原子上 ,得到共轭加成产物 2 ;当 1中的烷硫基为二甲硫基时 ,生成难以分离的混合物。

2-双烷硫基亚甲基-5,5-二甲基-1,3-环己二酮与Grignard试剂加成反应取向的初步研究

用具有不同烷硫基的2－双烷硫基亚甲基－5，5－二甲基－1，3－环已二酮与烯丙基、2－甲基烯丙基、苯基卤化镁等Grignard试剂反应，对加成反应取向进行了初步考察．2－双烷流基亚甲基－5，5－二甲基－1，3－环已二酮与烯丙基和2－甲基烯丙基的加成均得到1，2－加成产物；2－二甲硫基亚甲基－5，5－二甲基－1，3－环已二酮与苯基溴化镁反应可得1，4－加成产物．