We gratefully acknowledge the Swedish Research Council Formas for generous financial support.

메틸 -6- 옥소 -3,4,6- triphenylhexanoate 1. 그램 규모의 합성 <ol><li> 10 mbar에서, 1 시간 동안 40 ℃에서 회전 증발기에서 둥근 바닥 플라스크에 건조 1- 에틸 -3- 메틸이 미다 졸륨 아세테이트 (EMIMAc). </li><li> 건조 EMIMAc 2.1 g 및 1,3- 디 페닐 -2- 프로 펜 -1- 온 마그네틱 교반기가 구비 된 100 ㎖ 둥근 바닥 플라스크에 1.0 g을 추가한다. </li><li> 메탄올 2.019 mL의 플라스크에 신남 2.3 g을 넣고. </li><li> 실온 (22 ℃)에서 1 분 동안 교반하여 디클로로 메탄 60 mL의 혼합물에 용해. </li><li> 그 후 0.37 mL의 1.8 디아 자비의 추가 [5.4.0] 운덱 -7- 엔, 교반 혼합한다 (단계 1.4) 및 둥근 바닥 플라스크를 캡핑 (DBU). </li><li> 상온 (22 ° C에서)에서 500 rpm의 속도에서 자기 교반 막대로 교반 하였다. </li><li> 1 H NMR. 7.8 ppm의 영역에서 칼콘의 이중 결합의 실종 24 표정으로 반응 종료를 확인합니다. </li><li> 반응물에 도달 할 때<html> 완성 10 밀리바, 15 분 동안 20 ℃에서 회전 증발기에서 휘발성 물질을 제거한다. </li><li> 자기 교반 막대로 교반 EMIMAc을 용해 잔사에 50㎖의 메탄올을 첨가한다. </li><li> 30 분 동안 750 rpm의 속도에서 자기 교반 막대로 격렬하게 교반하여 플라스크의 벽에서 고형물을 제거한다. 필요할 경우, 벽에서 남은 고형물을 제거하기 위해 주걱을 사용한다. </li><li> 프릿 (기공 크기 3)의 혼합물을 필터링합니다. </li><li> 메탄올의 추가 20 ㎖로 세척. EMIMAc 재활용이 요구되는 경우 메탄올 성 여액을 증발시켰다. (2.1 단계). </li><li> 여전히 프릿에 부드럽게 주걱 작은 조각으로 (단계 1.11)에서 필터 케이크를 나누어 미리 칭량 둥근 바닥 플라스크에 분말 깔때기를 통해 고체를 전송하고, 진공하에 고체를 건조. </li><li> 플라스크의 무게를 측정하고 수율을 계산한다. </li><li> 1 H NMR (스텝 1.7)에 의해 생성물을 분석한다. 보고 스펙트럼 비교. (24) </li></ol>EMIMAc의 제목 &quot;&gt; 2. 재활용 <ol><li> 30 분 동안 40 ° C에서 10 밀리바의 감압 (단계 1.12)에서 메탄올 혼합물로부터 휘발성 물질을 제거한다. </li><li> EMIMAc가 있는지 확인하기 위해 1 시간 NMR 및 13 C NMR에 의해 생성 된 오일을 분석한다. (24) </li><li> 재활용 EMIMAc 단계 1.2부터 사용합니다. </li></ol> 3. 겔화 <ol><li> 원액의 제조 <ol><li> 메틸 -6- 옥소 -3,4,6- triphenylhexanoate (단계 1.15에서 제품) 및 유리 병에 자기 교반 막대의 200 mg을 추가합니다. 케토 에스테르를 용해 2.0 ml의 디클로로 메탄을 추가합니다. 모든 때까지 저어은 해산했다. </li></ol></li><li> 동결 <ol><li> 500㎖의 비이커에 헵탄 50 mL로 추가한다. 헵탄에 원액의 1.5 ML을 추가합니다. 적절한 혼합을 보장하고 겔화가 일어날 때까지 실온에서 교반없이 서 있도록 신속하게 교반한다. </li></ol></li></ol>

<ol>
	<li>Hallett, J. P., Welton, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Room-Temperature+Ionic+Liquids:+Solvents+for+Synthesis+and+Catalysis.+2.">Room-Temperature Ionic Liquids: Solvents for Synthesis and Catalysis. 2.</a> Chem. Rev. 111, 3508-3576 (2011).</li><li>Welton, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Room-Temperature+Ionic+Liquids.+Solvents+for+Synthesis+and+Catalysis.">Room-Temperature Ionic Liquids. Solvents for Synthesis and Catalysis.</a> Chem. Rev. 99, 2071-2084 (1999).</li><li>Vora, H. U., Wheeler, P., Rovis, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploiting+acyl+and+enol+azolium+intermediates+via+N-hetero-+cyclic+carbene-catalyzed+reactions+of+&#945;-reducible+aldehydes.">Exploiting acyl and enol azolium intermediates via N-hetero- cyclic carbene-catalyzed reactions of &#945;-reducible aldehydes.</a> Adv. Synth. Catal. 354, 1617-1639 (2012).</li><li>Holloczki, O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbenes+in+ionic+liquids.">Carbenes in ionic liquids.</a> New J. Chem. 34, 3004-3009 (2010).</li><li>Enders, D., Balensiefer, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nucleophilic+Carbenes+in+Asymmetric+Organocatalysis.">Nucleophilic Carbenes in Asymmetric Organocatalysis.</a> Acc. Chem. Res. 37, 534-541 (2004).</li><li>Enders, D., Niemeier, O., Henseler, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organocatalysis+by+N-Heterocyclic+Carbenes.">Organocatalysis by N-Heterocyclic Carbenes.</a> Chem. Rev. 107, 5606-5655 (2007).</li><li>List, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enamine+Catalysis+Is+a+Powerful+Strategy+for+the+Catalytic+Generation+and+Use+of+Carbanion+Equivalents.">Enamine Catalysis Is a Powerful Strategy for the Catalytic Generation and Use of Carbanion Equivalents.</a> Acc. Chem. Res. 37, 548-557 (2004).</li><li>Nair, V., Bindu, S., Sreekumar, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-Heterocyclic+carbenes:+Reagents,+not+just+ligands!.">N-Heterocyclic carbenes: Reagents, not just ligands!.</a> Angew. Chem. Int. Ed. 43, 5130-5135 (2004).</li><li>Marion, N., D&#236;ez-Gonz&#225;lez, S., Nolan, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-Heterocyclic+Carbenes+as+Organocatalysts.">N-Heterocyclic Carbenes as Organocatalysts.</a> Angew. Chem. Int. Ed. 46, 2988-3000 (2007).</li><li>Biju, A. T., Kuhl, N., Glorius, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extending+NHC-Catalysis:+Coupling+Aldehydes+with+Unconventional+Reaction+Partners.">Extending NHC-Catalysis: Coupling Aldehydes with Unconventional Reaction Partners.</a> Acc. Chem. Res. 44, 1182-1195 (2011).</li><li>Bugaut, X., Glorius, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organocatalytic+umpolung:+N-heterocyclic+carbenes+and+beyond.">Organocatalytic umpolung: N-heterocyclic carbenes and beyond.</a> Chem. Soc. Rev. 41, 3511-3522 (2012).</li><li>Davis, h. j., Forrester, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thiazolium-ion+based+organic+ionic+liquids+(OILs).1,2+Novel+OILs+which+promote+the+benzoin+condensation.">Thiazolium-ion based organic ionic liquids (OILs).1,2 Novel OILs which promote the benzoin condensation.</a> Tetrahedron Lett. 40, 1621-1622 (1999).</li><li>Xu, L. -. W., Gao, Y., Yin, J. -. J., Li, L., Xia, C. -. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+and+mild+benzoin+condensation+reaction+catalyzed+by+simple+1-N-alkyl-3-methylimidazolium+salts.">Efficient and mild benzoin condensation reaction catalyzed by simple 1-N-alkyl-3-methylimidazolium salts.</a> Tetrahedron Lett. 46, 5317-5320 (2005).</li><li>Jiang, F. S., Yu, H., Gao, G., Xie, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Benzoin+condensation+in+imidazolium+based+room-temperature+ionic+liquids.">Benzoin condensation in imidazolium based room-temperature ionic liquids.</a> Chin. Chem. Lett. 16, 321-324 (2005).</li><li>Estager, J., L&#233;v&#234;que, J. M., Turgis, R., Draye, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solventless+and+swift+benzoin+condensation+catalyzed+by+1-alkyl-3-methylimidazolium+ionic+liquids+under+microwave+irradiation.">Solventless and swift benzoin condensation catalyzed by 1-alkyl-3-methylimidazolium ionic liquids under microwave irradiation.</a> J. Mol. Catal. A: Chem. 256, 261-264 (2006).</li><li>Estager, J., L&#233;v&#234;que, J. -. M., Turgis, R., Draye, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neat+benzoin+condensation+in+recyclable+room-temperature+ionic+liquids+under+ultrasonic+activation.">Neat benzoin condensation in recyclable room-temperature ionic liquids under ultrasonic activation.</a> Tetrahedron Lett. 48, 755-759 (2007).</li><li>Orsini, M., Chiarotto, I., Elinson, M. N., Sotgiu, G., Inesi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Benzoin+condensation+in+1,3-dialkylimidazolium+ionic+liquids+via+electrochemical+generation+of+N-heterocyclic+carbene.">Benzoin condensation in 1,3-dialkylimidazolium ionic liquids via electrochemical generation of N-heterocyclic carbene.</a> Electrochem. Commun. 11, 1013-1017 (2009).</li><li>Dunn, M. H., Cole, M. L., Harper, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+an+ionic+liquid+solvent+on+the+synthesis+of+[gamma]-butyrolactones+by+conjugate+addition+using+NHC+organocatalysts.">Effects of an ionic liquid solvent on the synthesis of [gamma]-butyrolactones by conjugate addition using NHC organocatalysts.</a> RSC Advances. 2, 10160-10162 (2012).</li><li>Kelemen, Z., Holloczki, O., Nagy, J., Nyulaszi, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+organocatalytic+ionic+liquid.">An organocatalytic ionic liquid.</a> Org. Biomol. Chem. 9, 5362-5364 (2011).</li><li>Yu, F. -. L., Zhang, R. -. L., Xie, C. -. X., Yu, S. -. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+thermoregulated+phase-separable+triazolium+ionic+liquids+catalysts+and+application+for+Stetter+reaction.">Synthesis of thermoregulated phase-separable triazolium ionic liquids catalysts and application for Stetter reaction.</a> Tetrahedron. 66, 9145-9150 (2010).</li><li>Aupoix, A., Vo-Thanh, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solvent-free+synthesis+of+alkylthiazolium-based+ionic+liquids+and+their+use+as+catalysts+in+the+intramolecular+Stetter+reaction.">Solvent-free synthesis of alkylthiazolium-based ionic liquids and their use as catalysts in the intramolecular Stetter reaction.</a> Synlett. , 1915-1920 (2009).</li><li>Yu, F. -. L., Jiang, J. -. J., Zhao, D. -. M., Xie, C. -. X., Yu, S. -. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Imidazolium+chiral+ionic+liquid+derived+carbene-catalyzed+conjugate+umpolung+for+synthesis+of+[gamma]-butyrolactones.">Imidazolium chiral ionic liquid derived carbene-catalyzed conjugate umpolung for synthesis of [gamma]-butyrolactones.</a> RSC Advances. 3, 3996-4000 (2013).</li><li>Liu, D., Zhang, Y., Chen, E. Y. X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organocatalytic+upgrading+of+the+key+biorefining+building+block+by+a+catalytic+ionic+liquid+and+N-heterocyclic+carbenes.">Organocatalytic upgrading of the key biorefining building block by a catalytic ionic liquid and N-heterocyclic carbenes.</a> Green Chem. 14, 2738-2746 (2012).</li><li>Ta, L., Axelsson, A., Bijl, J., Haukka, M., Sund&#233;n, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ionic+Liquids+as+Precatalysts+in+the+Highly+Stereoselective+Conjugate+Addition+of+&#945;,&#946;-Unsaturated+Aldehydes+to+Chalcones.">Ionic Liquids as Precatalysts in the Highly Stereoselective Conjugate Addition of &#945;,&#946;-Unsaturated Aldehydes to Chalcones.</a> Chem. Eur. J. 20, 13889-13893 (2014).</li><li>Nair, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nucleophilic+Heterocyclic+Carbene+Catalyzed+Annulation+of+Enals+to+Chalcones+in+Methanol:+A+Stereoselective+Synthesis+of+Highly+Functionalized+Cyclopentanes.">Nucleophilic Heterocyclic Carbene Catalyzed Annulation of Enals to Chalcones in Methanol: A Stereoselective Synthesis of Highly Functionalized Cyclopentanes.</a> Org. Lett. 11, 2507-2510 (2009).</li><li>Ma, J., Huang, Y., Chen, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-Heterocyclic+carbene-catalyzed+(NHC)+three-component+domino+reactions:+highly+stereoselective+synthesis+of+functionalized+acyclic+&#1013;-ketoesters.">N-Heterocyclic carbene-catalyzed (NHC) three-component domino reactions: highly stereoselective synthesis of functionalized acyclic &#1013;-ketoesters.</a> Org. Biomol. Chem. 9, 1791-1798 (2011).</li><li>Domingo, L. R., Saez, J. A., Arno, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+DFT+study+on+the+NHC+catalysed+Michael+addition+of+enols+to+&#945;,&#946;-unsaturated+acyl-azoliums.+A+base+catalysed+C-C+bond-formation+step.">A DFT study on the NHC catalysed Michael addition of enols to &#945;,&#946;-unsaturated acyl-azoliums. A base catalysed C-C bond-formation step.</a> Org. Biomol. Chem. 12, 895-904 (2014).</li><li>Kaeobamrung, J., Mahatthananchai, J., Zheng, P., Bode, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Enantioselective+Claisen+Rearrangement+Catalyzed+by+N-Heterocyclic+Carbenes.">An Enantioselective Claisen Rearrangement Catalyzed by N-Heterocyclic Carbenes.</a> J. Am. Chem. Soc. 132, 8810-8812 (2010).</li><li>Zweep, N., van Esch, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Functional Molecular Gels. , 1-29 (2014).</li><li>Chiang, P. -. C., Kaeobamrung, J., Bode, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enantioselective,+Cyclopentene-Forming+Annulations+via+NHC-Catalyzed+Benzoin&#8722;Oxy-Cope+Reactions.">Enantioselective, Cyclopentene-Forming Annulations via NHC-Catalyzed Benzoin&#8722;Oxy-Cope Reactions.</a> J. Am. Chem. Soc. 129, 3520-3521 (2007).</li></ol>

The authors have nothing to disclose.

케토 에스테르 (3)의 X 선 분석 및 보데 및 동료 (30)에 의해 제안 된 기전 조사하여 결정 안티 배위에 기초하기 반응 경로는 (도 5)를 제안한다. IL의 탈 양성자는 NHC 종을 생성; NHC는 Breslow 중간 I. Breslow 중간체 형성하는 불포화 알데히드와 반응은 칼콘 디엔 II를 형성하도록 상호 벤조 반응에서 반응한다. 중급 II는 안티 지향 입체 센터 III를 설정, 보트 전이 상태 (TS)...

<img alt="TOC (1)" src="/files/ftp_upload/53213/53213TOC.jpg" /> (위) 1,6- ketoesters의 3 성분계 합성 : 저 분자량 젤 레이터의 새로운 클래스. 이온 성 액체 (ILS)의 높은 안정성, 낮은 휘발성, 비 - 가연성을 가지므로 재활용 안전한 반응 매체와 이상적인 용매로서 관심을 표현하고있다. 1-3 디 알킬 imidazoliums은 이온 성 액체의 특정 유형임을, 염기의 존재하에 , organocatalysis의 분야에서 N- 헤테로 카르 벤 (NHC). (4)을 렌더링하기 위해 탈 수있는, NHCs, 서로 다른 반응 경로에서 작동, 일반적인 반응의 넓은 범위에서 광범위하게 사용을 발견했다. 5-11 그럼에도 불구하고, 대한 IL 및 CC 결합 formin 사이의 연결G NHC-촉매는 상대적으로 미개척입니다. 그럼에도 불구하고, IL을으로부터 유도 NHCs 그러한 벤조 축합 STETTER 반응으로 형성 반응 CC 결합을 촉진하는 것으로보고되고있다. 예를 들어 12-22, 데이비스 외. N - 알킬 thiazoliums로부터 유도의 IL이있는 precatalysts 역할을 보여 주었다 벤즈알데히드로부터 형성 벤조. 12 최근 첸과 동료 IL 기반 졸리움을 사용하여 이러한 개념을 확장, 1- 에틸 -3- 메틸이 미다 졸륨 아세테이트 (EMIMAc) &#39;5,5 생성 5- hydroxymethylfurfural (HMF)에 벤조 축합을 수행하는 디 대한 IL 상업적으로 사용할 수 있으며, NHCs을 생성하는 저렴한 방법을 제공하는 점을 감안 (히드 록시 메틸) furoin (DHMF). (23), 우리는 반응에 대한 IL의 다른 유형 수행 할 수있는 것을 조사에 관심이 있었다. 이를 위해, 디 알킬 imidazoliums 효율적 공식 공액 additi에 precatalysts로서 사용될 수 있다는 것을 발견불포화 알데히드에 1,6- ketoesters을주는 칼콘 (그림 1)에. 가장 효율적인 IL, EMIMAc는 신남 및 칼콘 사이 높은 입체 선택적 반응을 촉진한다. 반응은 안티 -diastereomer에 대한 높은 선호도 발생 및 1,6- ketoesters은 최대 92 % 수율로 분리 할 수있다. 24,25,26 <img alt="그림 1" src="/files/ftp_upload/53213/53213fig1.jpg" /> 그림 1 : 세 가지 구성 요소, 칼콘에 신남의 입체 추가 IL-매개.

<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.

상기 예시 된 바와 같이, EMIMAc은 칼콘에 α, β 불포화 알데히드 공식 공액 또한 예비 촉매 역할을한다. 1- 에틸 -3- 메틸이 미다 졸륨 클로라이드 (EMIMCl) 및 1- 부틸 -3- 메틸이 미다 졸륨 클로라이드 (BMIMCl)와 같은 다른 시판 졸리움 계의 IL은 조사했다, 그러나, 아세테이트 음이온이있을 수 있음을 나타내는 낮은 수율로 진행 이들 반응 반응성 (표 1, 항목 1-3) 중요. 27, 28 *</s...

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.

이온 성 액체에 의해 매개 1,6- Ketoesters의 높은 입체 선택적 합성 : 저 분자량 젤 레이터의 새로운 클래스에 빠른 액세스를 가능하게하는 3 요소 반응

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 ...

highly-stereoselective-synthesis-16-ketoesters-mediated-ionic-liquids

Research

JoVE Journal

Chemistry

8.6K 조회수.  Chalmers University of Technology. 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. 

비디오: 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

Preparation and Use of Samarium Diiodide (SmI2) in Organic Synthesis: The Mechanistic Role of HMPA and Ni(II) Salts in the Samarium Barbier Reaction

Although initially considered an esoteric reagent, SmI2 has become a common tool for synthetic organic chemists. SmI2 is generated through the addition of molecular iodine to samarium metal in THF.1,2-3 It is a mild and selective single electron reductant and its versatility is a result of its ability to initiate a wide range of reductions including C-C bond-forming and cascade or sequential reactions. SmI2 can reduce a variety of functional groups including sulfoxides and sulfones, phosphine oxides, epoxides, alkyl and aryl halides, carbonyls, and conjugated double bonds.2-12 One of the fascinating features of SmI-2-mediated reactions is the ability to manipulate the outcome of reactions through the selective use of cosolvents or additives. In most instances, additives are essential in controlling the rate of reduction and the chemo- or stereoselectivity of reactions.13-14 Additives commonly utilized to fine tune the reactivity of SmI2 can be classified into three major groups: (1) Lewis bases (HMPA, other electron-donor ligands, chelating ethers, etc.), (2) proton sources (alcohols, water etc.), and (3) inorganic additives (Ni(acac)2, FeCl3, etc).3
Understanding the mechanism of SmI2 reactions and the role of the additives enables utilization of the full potential of the reagent in organic synthesis. The Sm-Barbier reaction is chosen to illustrate the synthetic importance and mechanistic role of two common additives: HMPA and Ni(II) in this reaction. The Sm-Barbier reaction is similar to the traditional Grignard reaction with the only difference being that the alkyl halide, carbonyl, and Sm reductant are mixed simultaneously in one pot.1,15 Examples of Sm-mediated Barbier reactions with a range of coupling partners have been reported,1,3,7,10,12 and have been utilized in key steps of the synthesis of large natural products.16,17 Previous studies on the effect of additives on SmI2 reactions have shown that HMPA enhances the reduction potential of SmI2 by coordinating to the samarium metal center, producing a more powerful,13-14,18 sterically encumbered reductant19-21 and in some cases playing an integral role in post electron-transfer steps facilitating subsequent bond-forming events.22 In the Sm-Barbier reaction, HMPA has been shown to additionally activate the alkyl halide by forming a complex in a pre-equilibrium step.23
Ni(II) salts are a catalytic additive used frequently in Sm-mediated transformations.24-27 Though critical for success, the mechanistic role of Ni(II) was not known in these reactions. Recently it has been shown that SmI2 reduces Ni(II) to Ni(0), and the reaction is then carried out through organometallic Ni(0) chemistry.28
These mechanistic studies highlight that although the same Barbier product is obtained, the use of different additives in the SmI2 reaction drastically alters the mechanistic pathway of the reaction. The protocol for running these SmI2-initiated reactions is described.

Preparation and Use of Samarium Diiodide SmI2 in Organic Synthesis: The Mechanistic Role of HMPA and NiII Salts in the Samarium Barbier Reaction

A straightforward procedure for the preparation of samarium diiodide (SmI2) in THF is described. The role of two main additives namely hexamethylphosphoramide (HMPA) and Ni(acac)2 in Sm mediated reactions is demonstrated in the Sm-Barbier reaction.

준비와 사마륨 Diiodide 이용 (SMI<sub&gt; 2</sub&gt;) 유기 합성의 : 사마륨 Barbier 반응에 HMPA과 니켈 (II) 소금의 기계론의 역할

Although initially considered an esoteric reagent, SmI2 has become a common tool for synthetic organic chemists. SmI2 is generated through the addition of ...

연구

화학

Synthesis and Reaction Chemistry of Nanosize Monosodium Titanate

This paper describes the synthesis and peroxide-modification of nanosize monosodium titanate (nMST), along with an ion-exchange reaction to load the material with Au(III) ions. The synthesis method was derived from a sol-gel process used to produce micron-sized monosodium titanate (MST), with several key modifications, including altering reagent concentrations, omitting a particle seed step, and introducing a non-ionic surfactant to facilitate control of particle formation and growth. The resultant nMST material exhibits spherical-shaped particle morphology with a monodisperse distribution of particle diameters in the range from 100 to 150&#160;nm. The nMST material was found to have a Brunauer-Emmett-Teller (BET) surface area of 285 m2g-1, which is more than an order of magnitude higher than the micron-sized MST. The isoelectric point of the nMST measured 3.34 pH units, which is a pH unit lower than that measured for the micron-size MST. The nMST material was found to serve as an effective ion exchanger under weakly acidic conditions for the preparation of an Au(III)-exchange nanotitanate. In addition, the formation of the corresponding peroxotitanate was demonstrated by reaction of the nMST with hydrogen peroxide.

The surfactant mediated sol-gel synthesis of nanosized monosodium titanate is described, along with preparation of the corresponding peroxide modified material. An ion-exchange reaction with Au(III) is also presented.

This paper describes the synthesis and peroxide-modification of nanosize monosodium titanate (nMST), along with an ion-exchange reaction to load the ...

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

Due to their abundance in natural clay and potential applications in advanced materials, discotic nanoparticles are of interest to scientists and engineers. Growth of such anisotropic nanocrystals through a simple chemical method is a challenging task. In this study, we fabricate discotic nanodisks of zirconium phosphate [Zr(HPO4)2&#183;H2O] as a model material using hydrothermal, reflux and microwave-assisted methods. Growth of crystals is controlled by duration time, temperature, and concentration of reacting species. The novelty of the adopted methods is that discotic crystals of size ranging from hundred nanometers to few micrometers can be obtained while keeping the polydispersity well within control. The layered discotic crystals are converted to monolayers by exfoliation with tetra-(n)-butyl ammonium hydroxide [(C4H9)4NOH, TBAOH]. Exfoliated disks show isotropic and nematic liquid crystal phases. Size and polydispersity of disk suspensions is highly important in deciding their phase behavior.

A two dimensional model material of discotic zirconium phosphate was developed. The inorganic crystal with lamellar structure was synthesized by hydrothermal, reflux, and microwave-assisted methods. On exfoliation with organic molecules, layered crystals can be converted to monolayers, and nematic liquid crystal phase was formed at sufficient concentration of monolayers.

합성 및 디스코 틱 지르코늄 인산염의 각질 제거는 콜로이드 액체 크리스탈을 구하는

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

This study presents a novel two-stage thiol-acrylate Michael addition-photopolymerization (TAMAP) reaction to prepare main-chain liquid-crystalline elastomers (LCEs) with facile control over network structure and programming of an aligned monodomain. Tailored LCE networks were synthesized using routine mixing of commercially available starting materials and pouring monomer solutions into molds to cure. An initial polydomain LCE network is formed via a self-limiting thiol-acrylate Michael-addition reaction. Strain-to-failure and glass transition behavior were investigated as a function of crosslinking monomer, pentaerythritol tetrakis(3-mercaptopropionate) (PETMP). An example non-stoichiometric system of 15 mol% PETMP thiol groups and an excess of 15 mol% acrylate groups was used to demonstrate the robust nature of the material. The LCE formed an aligned and transparent monodomain when stretched, with a maximum failure strain over 600%. Stretched LCE samples were able to demonstrate both stress-driven thermal actuation when held under a constant bias stress or the shape-memory effect when stretched and unloaded. A permanently programmed monodomain was achieved via a second-stage photopolymerization reaction of the excess acrylate groups when the sample was in the stretched state. LCE samples were photo-cured and programmed at 100%, 200%, 300%, and 400% strain, with all samples demonstrating over 90% shape fixity when unloaded. The magnitude of total stress-free actuation increased from 35% to 115% with increased programming strain. Overall, the two-stage TAMAP methodology is presented as a powerful tool to prepare main-chain LCE systems and explore structure-property-performance relationships in these fascinating stimuli-sensitive materials.

A novel methodology is presented to synthesize and program main-chain liquid-crystalline elastomers using commercially available starting monomers. A wide range of thermomechanical properties was tailored by adjusting the amount of crosslinker, while the actuation performance was dependent on the amount of applied strain during programming.

이단 티올 레이트 반응을 이용하여 프로그래밍 주쇄 액정 엘라스토머의 합성

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

Fluorescent nanocrystals, specifically quantum dots, have been a useful tool for many biomedical applications. For successful use in biological systems, quantum dots should be highly fluorescent and small/monodisperse in size. While commonly used cadmium-based quantum dots possess these qualities, they are potentially toxic due to the possible release of Cd2+ ions through nanoparticle degradation. Indium-based quantum dots, specifically InP/ZnS, have recently been explored as a viable alternative to cadmium-based quantum dots due to their relatively similar fluorescence characteristics and size. The synthesis presented here uses standard hot-injection techniques for effective nanoparticle growth; however, nanoparticle properties such as size, emission wavelength, and emission intensity can drastically change due to small changes in the reaction conditions. Therefore, reaction conditions such temperature, reaction duration, and precursor concentration should be maintained precisely to yield reproducible products. Because quantum dots are not inherently soluble in aqueous solutions, they must also undergo surface modification to impart solubility in water. In this protocol, an amphiphilic polymer is used to interact with both hydrophobic ligands on the quantum dot surface and bulk solvent water molecules. Here, a detailed protocol is provided for the synthesis of highly fluorescent InP/ZnS quantum dots that are suitable for use in biomedical applications.

In this protocol, the synthesis of Cd-free InP/ZnS quantum dots (QDs) is detailed. InP-based QDs are gaining popularity due to the toxicity of Cd2+ ions that may be released through nanoparticle degradation. After synthesis, QDs are solubilized in water using an amphiphilic polymer for use in biomedical applications.

바이오 메디컬 응용 프로그램에 적합 InP를 /의 ZnS 양자점 CD-자유의 합성

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

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins with the synthesis of a hydrophilic poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) homopolymer using reversible addition-fragmentation chain-transfer (RAFT) polymerization. Under mild visible light irradiation (&#955; = 460 nm, 0.7 mW/cm2), this macro-chain transfer agent (macro-CTA) in the presence of a ruthenium based photoredox catalyst, Ru(bpy)3Cl2 can be chain extended with a second monomer to form a well-defined block copolymer in a process known as Photoinduced Electron Transfer RAFT (PET-RAFT). When PET-RAFT is used to chain extend POEGMA with benzyl methacrylate (BzMA) in ethanol (EtOH), polymeric nanoparticles with different morphologies are formed in situ according to a polymerization-induced self-assembly (PISA) mechanism. Self-assembly into nanoparticles presenting POEGMA chains at the corona and poly(benzyl methacrylate) (PBzMA) chains in the core occurs in situ due to the growing insolubility of the PBzMA block in ethanol. Interestingly, the formation of highly pure worm-like micelles can be readily monitored by observing the onset of a highly viscous gel in situ due to nanoparticle entanglements occurring during the polymerization. This process thereby allows for a more reproducible synthesis of worm-like micelles simply by monitoring the solution viscosity during the course of the polymerization. In addition, the light stimulus can be intermittently applied in an ON/OFF manner demonstrating temporal control over the nanoparticle morphology.

This article describes a process for producing polymeric self-assembled nanoparticles using visible light mediated dispersion polymerization. Using low energy visible light to control the polymerization allows for the reproducible formation of self-assembled worm-like micelles at high solids content.

Photoredox 촉매를 사용하여 가시 광선 중재 분산 중합에 의해 웜 형상 미셀 손쉬운 합성

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

Controlled Synthesis and Fluorescence Tracking of Highly Uniform Poly(N-isopropylacrylamide) Microgels

Stimuli-sensitive poly(N-isopropylacrylamide) (PNIPAM) microgels have various prospective practical applications and uses in fundamental research. In this work, we use single particle tracking of fluorescently labeled PNIPAM microgels as a showcase for tuning microgel size by a rapid non-stirred precipitation polymerization procedure. This approach is well suited for prototyping new reaction compositions and conditions or for applications that do not require large amounts of product. Microgel synthesis, particle size and structure determination by dynamic and static light scattering are detailed in the protocol. It is shown that the addition of functional comonomers can have a large influence on the particle nucleation and structure. Single particle tracking by wide-field fluorescence microscopy allows for an investigation of the diffusion of labeled tracer microgels in a concentrated matrix of non-labeled microgels, a system not easily investigated by other methods such as dynamic light scattering.

Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels

Non-stirred precipitation polymerization provides a rapid, reproducible prototyping approach to the synthesis of stimuli-sensitive poly(N-isopropylacrylamide) microgels of narrow size distribution. In this protocol synthesis, light scattering characterization and single particle fluorescence tracking of these microgels in a wide-field microscopy setup are demonstrated.

제어 합성 및 매우 균일 한 폴리 형광 추적 (<em&gt; N</em&gt; 이소 프로필 아크릴 아미드) 미크로 겔

Stimuli-sensitive poly(N-isopropylacrylamide) (PNIPAM) microgels have various prospective practical applications and uses in fundamental research. In this ...

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

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 crystals (ILCs). Taking advantages of the high specificity of XB for haloperfluorocarbons and the ability of anions to act as XB-acceptors, we obtained supramolecular complexes based on 1-alkyl-3-methylimidazolium iodides and iodoperfluorocarbons, overcoming the well-known immiscibility between hydrocarbons (HCs) and perfluorocarbons (PFCs). The high directionality of the XB combined with the fluorophobic effect, allowed us to obtain enantiotropic liquid crystals where a rigid, non-aromatic, XB supramolecular anion acts as mesogenic core.
X-ray structure analysis of the complex between 1-ethyl-3-methylimidazolium iodide and iodoperfluorooctane showed the presence of a layered structure, which is a manifestation of the well-known tendency to segregation of perfluoroalkyl chains. This is consistent with the observation of smectic mesophases. Moreover, all the reported complexes melt below 100 &#176;C, and most are mesomorphic even at room temperature, despite that the starting materials were non-mesomorphic in nature.
The supramolecular strategy reported here provides new design principles for mesogen design allowing a totally new class of functional materials.

A protocol for the synthesis of a new type of mesogens, based on the halogen-bonded supramolecular anion [CnF2n+1-I&#183;&#183;&#183;I&#183;&#183;&#183;I-CnF2n+1]&#8722;, is reported.

분자 재료를에서: 할로겐 결합을 통해 새로운 이오니아 액체 크리스탈 엔지니어링

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 ...

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

The use of nanoprobes such as gold, silver, silica or iron-oxide nanoparticles as detection reagents in bioanalytical assays can enable high sensitivity and convenient colorimetric readout. However, high densities of nanoparticles are typically needed for detection. The available synthesis-based enhancement protocols are either limited to gold and silver nanoparticles or rely on precise enzymatic control and optimization. Here, we present a protocol to enhance the colorimetric readout of gold, silver, silica, and iron oxide nanoprobes. It was observed that the colorimetric signal can be improved by up to a 10000-fold factor. The basis for such signal enhancement strategies is the chemical reduction of Au3+ to Au0. There are several chemical reactions that enable the reduction of Au3+ to Au0. In the protocol, Good&#39;s buffers and H2O2 are used and it is possible to favor the deposition of Au0 onto the surface of existing nanoprobes, in detriment of the formation of new gold nanoparticles. The protocol consists of the incubation of the microarray with a solution consisting of chloroauric acid and H2O2 in 2-(N-morpholino)ethanesulfonic acid pH 6 buffer following the nanoprobe-based detection assay. The enhancement solution can be applied to paper and glass-based sensors. Moreover, it can be used in commercially available immunoassays as demonstrated by the application of the method to a commercial allergen microarray. The signal development requires less than 5 min of incubation with the enhancement solution and the readout can be assessed by naked eye or low-end image acquisition devices such as a table-top scanner or a digital camera.

Rapid Nanoprobe Signal Enhancement by In Situ Gold Nanoparticle Synthesis

In this work, a protocol for signal enhancement of nanoprobe-based biosensing is presented. The protocol is based on the reduction of chloroauric acid onto the surface of existing nanoprobes that consist of gold, silver, silica or iron-oxide nanoparticles.

에 라 골드 나노 입자 합성에 의해 급속 한 Nanoprobe 신호 향상

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

Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain

Barium titanate (BaTiO3, hereafter BT) is an established ferroelectric material first discovered in the 1940s and still widely used because of its well-balanced ferroelectricity, piezoelectricity, and dielectric constant. In addition, BT does not contain any toxic elements. Therefore, it is considered to be an eco-friendly material, which has attracted considerable interest as a replacement for lead zirconate titanate (PZT). However, bulk BT loses its ferroelectricity at approximately 130 &#176;C, thus, it cannot be used at high temperatures. Because of the growing demand for high-temperature ferroelectric materials, it is important to enhance the thermal stability of ferroelectricity in BT. In previous studies, strain originating from the lattice mismatch at hetero-interfaces has been used. However, the sample preparation in this approach requires complicated and expensive physical processes, which are undesirable for practical applications.
In this study, we propose a chemical synthesis of a porous material as an alternative means of introducing strain. We synthesized a porous BT thin film using a surfactant-assisted sol-gel method, in which self-assembled amphipathic surfactant micelles were used as an organic template. Through a series of studies, we clarified that the introduction of pores had a similar effect on distorting the BT crystal lattice, to that of a hetero-interface, leading to the enhancement and stabilization of ferroelectricity. Owing to its simplicity and cost effectiveness, this fabrication process has considerable advantages over conventional methods.

Here, we present a protocol for the synthesis of porous barium titanate (BaTiO3) thin film by a surfactant-assisted sol-gel method, in which self-assembled amphipathic surfactant micelles are used as an organic template.