Name: highly stereoselective synthesis of 1,6-ketoesters mediated by ionic liquids: a three-component reaction enabling rapid access to a new class of low molecular weight gelators
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甲基-6-氧代-3,4,6- triphenylhexanoate 1.革兰氏规模合成<ol><li>干1-乙基-3-甲基咪唑鎓乙酸盐（EMIMAc）在10毫巴，40℃下1小时，在旋转蒸发器的圆底烧瓶中。 </li><li>添加2.1克干燥EMIMAc和1.0克1,3-二苯基-2-丙烯-1-酮向100毫升圆底烧瓶配备有磁力搅拌器。 </li><li>添加2.019毫升甲醇和2.3克肉桂烧瓶中。 </li><li>在室温（22℃）搅拌1分钟溶解在60毫升二氯甲烷的混合物中。 </li><li>接着添加0.37 ml的1.8二氮杂二环[5.4.0]?...

<ol>
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基于由酮酯3的X射线分析和对所提出的Bode和同事30的机械调查确定反 -构型的下述反应路径建议（图5）。白细胞介素脱质子产生NHC种;所述NHC反应与不饱和醛形成布瑞斯罗夫中间体I中布瑞斯罗夫中间和在跨安息香反应的查耳酮反应形成二烯二。中级II经过转乘船过渡态（TS）的氧Cope重排，设置防取向的手性中心III。互变异构之后，酰基氮鎓IV与甲醇反应来交付产品?...

<img alt="TOC 1" src="/files/ftp_upload/53213/53213TOC.jpg" /> （以上）的1,6-酮酯三组分合成：一类新的低分子量胶凝剂。 离子液体（离子液体）具有高稳定性，低挥发性，不可燃性，并因此呈现关注，因为安全的反应介质和理想的溶剂进行回收。1-3二烷基咪唑鎓是一个特定类型的离子液体，在碱的存在下可以去质子化，以使一个N-杂环卡宾（NHC）。4在有机催化的领域中，的NHCs，根据不同的反应路径操作时，已经被广泛的使用在广泛的通用反应。5-11 尽管如此，ILS和CC键formin之间的连接摹NHC催化相对未开发的。尽管如此，从的NHCs离子液体衍生已经报道了催化CC键形成反应，如苯偶姻缩合和施德达反应。12-22。例如，Davis等人已经表明，从N-烷基thiazoliums衍生离子液体作为在预催化剂形成苯甲醛安息香12 最近，Chen和同事扩展使用基于IL咪唑这个概念，1-乙基-3-甲基咪唑鎓乙酸盐（EMIMAc），对5-羟甲基糠醛（HMF）执行安息香缩合以生成5,5&#39; -二（羟甲基）furoin（DHMF）。23由于离子液体可以买到，报价产生NHC的的一种廉价的方式，我们有兴趣在研究什么其他类型的反应，离子液体可以执行。为此，我们发现，二烷基咪唑鎓可有效用作在正规共轭additi预催化剂上的不饱和醛以查耳酮（图1），得到1,6-酮酯。最有效的IL，EMIMAc，促进肉桂醛和查尔之间的高立体选择性反应。发生反应以高偏爱反 -非对映和1,6-酮酯可以分离在产率高达92％。24,25,26 <img alt="图1" src="/files/ftp_upload/53213/53213fig1.jpg" /> 图1：IL-介导的三组分，立体选择性加成肉桂醛以查耳酮。

<table>
	<tbody>
		<tr>
			<td>1-ethyl-3-methyl imidazolium acetate</td>
			<td>Aldrich</td>
			<td>51053-100G-F</td>
			<td>Produced by BASF &#8805;90%, dried on a rotary evaporated before use (10 mBar, 40 &#176;C, 1h) 
			CAS NUMBER: 143314-17-4</td>
		</tr>
		<tr>
			<td>1,3-diphenyl-2-propen-1-one</td>
			<td>Aldrich</td>
			<td>11970-100G</td>
			<td>98.0% 
			CAS NUMBER: 94-41-7</td>
		</tr>
		<tr>
			<td>trans-cinnamaldehyde&#160;</td>
			<td>Aldrich</td>
			<td>C80687-25G</td>
			<td>99%, stored under nitrogen prior to use 
			CAS NUMBER: 14371-10-9</td>
		</tr>
		<tr>
			<td>1,8-Diazobicyclo[5.4.0]undec-7-ene</td>
			<td>Aldrich</td>
			<td>139009-25G</td>
			<td>98% 
			CAS NUMBER: 6674-22-2</td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Sigma-Aldrich</td>
			<td>32213N-2.5L</td>
			<td>puriss. P.a., ACS reagent, reag. ISO, reag. Ph. Eur. &#8805;99.8% (GC) 
			CAS NUMBER: 67-56-1</td>
		</tr>
		<tr>
			<td>Dichloromethane</td>
			<td>Fischer Chemical</td>
			<td>D/1852/17X</td>
			<td>Analytic reagent grade, stabilized with amylene 
			CAS NUMBER:9/2/1975</td>
		</tr>
		<tr>
			<td>n-Heptane</td>
			<td>Fischer Chemical</td>
			<td>H/0160/17X</td>
			<td>Analytic reagent grade 
			CAS NUMBER: 142-82-5</td>
		</tr>
	</tbody>
</table>

highly stereoselective synthesis of 1,6-ketoesters mediated by ionic liquids: a three-component reaction enabling rapid access to a new class of low molecular weight gelators

In organic chemistry ionic liquids (ILs) have emerged as safe and recyclable reaction solvents. In the presence of a base ILs can be deprotonated to form catalytically active N-Heterocyclic Carbenes (NHCs). Here we have used ILs as precatalysts in the addition of &#945;,&#946;-unsaturated aldehydes to chalcones to form 1,6-ketoesters, incorporating an anti-diphenyl moiety in a highly stereoselective fashion. The reaction has a broad substrate scope and several functional groups and heteroaromatics can be integrated into the ketoester backbone in generally good yields with maintained stereoselectivity. The reaction protocol is robust and scalable. The starting materials are inexpensive and the products can be obtained after simple filtration, avoiding solvent-demanding chromatography. Furthermore, the IL can be recycled up to 5 times without any loss of reactivity. Moreover, the 1,6-ketoester end product is a potent gelator in several hydrocarbon based solvents. The method enables rapid access to and evaluation of a new class of low molecular weight gelators (LMWGs) from recyclable and inexpensive starting materials.

如上述例举EMIMAc充当在正规共轭加成α，β不饱和醛与查耳酮一个前段催化剂。其它市售咪唑鎓基的离子液体，例如1-乙基-3-甲基咪唑氯化物（EMIMCl）和1-丁基-3-甲基咪唑氯化物（BMIMCl）也进行了研究，然而，这些反应进行较低的产率，表明乙酸根阴离子可以是为反应性（ 表1，进入1-3）很重要。27,28 * *阴离子该反应中的作用是在目前还不清楚?...

Watch this Scientific Journal Video about Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

Ionic liquids (ILs) mediate fast, simple and cheap access to 1,6-ketoesters in high diastereoselectivities and good yields. The reaction protocol is robust and the 1,6-ketoesters can be obtained in gram scale after a simple filtration protocol. Moreover, the 1,6-ketoesters are potent gelators in hydrocarbon solvents.

1,6-酮酯高立体选择性合成离子液体介导：三组分反应启用快速进入低分子量胶凝剂的新型类

In organic chemistry ionic liquids (ILs) have emerged as safe and recyclable reaction solvents. In the presence of a base ILs can be deprotonated to form ...

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Synthesis and Exfoliation of Discotic Zirconium Phosphates to Obtain Colloidal Liquid Crystals

合成与盘状磷酸盐锆剥落获取胶体液晶

Due to their abundance in natural clay and potential applications in advanced materials, discotic nanoparticles are of interest to scientists and ...

Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction

的可编程主链液晶性弹性体用双级硫醇丙烯酸酯反应合成

This study presents a novel two-stage thiol-acrylate Michael addition-photopolymerization (TAMAP) reaction to prepare main-chain liquid-crystalline ...

Synthesis of Cd-free InP/ZnS Quantum Dots Suitable for Biomedical Applications

镉免费的InP /硫化锌量子点的合成适合生物医学应用

Fluorescent nanocrystals, specifically quantum dots, have been a useful tool for many biomedical applications. For successful use in biological systems, ...

Facile Synthesis of Worm-like Micelles by Visible Light Mediated Dispersion Polymerization Using Photoredox Catalyst

使用Photoredox催化剂蠕虫状胶束的简便合成可见光介导的分散聚合

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins ...

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

从分子到材料: 通过卤素键合工程新的离子液体晶体

Herein, we demonstrate that a bottom-up approach, based on halogen bonding (XB), can be successfully applied for the design of a new type of ionic liquid ...

Fabrication and Testing of Catalytic Aerogels Prepared Via Rapid Supercritical Extraction

快速超临界萃取制备催化气凝胶的制备与试验研究

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three ...

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

原位金纳米粒子合成快速 Nanoprobe 信号增强

The use of nanoprobes such as gold, silver, silica or iron-oxide nanoparticles as detection reagents in bioanalytical assays can enable high sensitivity ...