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Henry Reaction (henry + reaction)
Selected AbstractsA Highly Diastereoselective Tertiary Amine-Catalyzed Cascade Michael,Michael,Henry Reaction between Nitromethane, Activated Alkenes and ,,,-Unsaturated Carbonyl CompoundsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1 2010Bo Zhang Abstract A new tertiary amine-catalyzed cascade Michael,Michael,Henry reaction between nitromethane, a doubly activated alkene and an ,,,-unsaturated carbonyl compound is described, which provides a convenient and efficient synthesis for densely functionalized cyclohexanes and some bicyclic compounds in moderate to excellent yields with high diastereoselectivity. [source] Catalytic Asymmetric Direct Henry Reaction of Ynals: Short Syntheses of (2S,3R)-(+)-Xestoaminol,C and (,)-Codonopsinines,ANGEWANDTE CHEMIE, Issue 41 2010Dr. Daisuke Uraguchi Drei sind ein guter Start: Eine Reihe optisch aktiver anti -,-Nitropropargylalkohole wurde durch die katalytische stereoselektive Addition von Nitroalkanen an Inale erhalten. Diese direkte Henry-Reaktion von Inalen eröffnete einen raschen Zugang zu drei Naturstoffen über Transformationen der Kohlenstoff-Kohlenstoff-Dreifachbindung. [source] ChemInform Abstract: Catalytic Asymmetric Domino Michael,Henry Reaction: Enantioselective Access to Bicycles with Consecutive Quaternary Centers by Using Bifunctional Catalysts.CHEMINFORM, Issue 34 2010Magnus Rueping Abstract A bifunctional, cinchonidine-based, thiourea catalyst is shown to catalyze the enantioselective domino Michael,Henry reaction of cyclohexadienone (I) with various ,-nitrostyrenes. [source] ChemInform Abstract: Brucine-Derived Amino Alcohol Catalyzed Asymmetric Henry Reaction: An Orthogonal Enantioselectivity Approach.CHEMINFORM, Issue 20 2010Hun Young Kim Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Diastereo- and Enantioselective Direct Henry Reaction of Pyruvates Mediated by Chiral P-Spiro Tetraaminophosphonium Salts.CHEMINFORM, Issue 15 2010Daisuke Uraguchi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: 2-Quinolinecarboxaldehyde: An Unusual Partner in the Henry Reaction and Subsequent Elimination.CHEMINFORM, Issue 1 2009Ashley Nomland Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Investigation of DNA as a Catalyst for Henry Reaction in Water.CHEMINFORM, Issue 51 2008Jinmin Fan Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: A New, Readily Available Double-Component System for Asymmetric Henry Reaction.CHEMINFORM, Issue 28 2008Wuzu Ha Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Henry Reaction and 1,4-Addition of Nitroalkanes to ,,,-Unsaturated Carbonyl Compounds under the Influence of MS 4 Å in DMSO.CHEMINFORM, Issue 42 2007Takeshi Oriyama Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] ChemInform Abstract: Effect of Ligand Structure on the Zinc-Catalyzed Henry Reaction.CHEMINFORM, Issue 49 2002(-)-Arbutamine., Asymmetric Syntheses of (-)-Denopamine Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] A Highly Effective Bis(sulfonamide),Diamine Ligand: A Unique Chiral Skeleton for the Enantioselective Cu-Catalyzed Henry ReactionCHEMISTRY - A EUROPEAN JOURNAL, Issue 28 2010Wei Jin A skeleton in the closet! As a unique chiral skeleton, the newly developed bis(sulfonamide),diamine, which contains both diamine and bis(sulfonamide) moieties, was a highly effective ligand for the asymmetric Cu(OAc)2 -catalyzed Henry reaction between nitromethane and aldehydes with a low catalyst loading at room temperature (see scheme). Both aliphatic and aromatic aldehydes gave excellent enantioselectivities of up to 99,%,ee. [source] One-Pot Synthesis of Pentasubstituted Cyclohexanes by a Michael Addition Followed by a Tandem Inter,Intra Double Henry ReactionCHEMISTRY - A EUROPEAN JOURNAL, Issue 27 2009Luis García, Ruano Prof. Abstract Michael, Henry, and Henry: A new one-pot reaction of ,,,-unsaturated aldehydes and ,-dicarbonyls, which involves a Michael reaction catalyzed by diarylprolinol ethers and an inter,intramolecular Henry tandem reaction catalyzed by TBAF (see scheme), has been developed. The reaction proceeds in high enantio- and diastereoselectivity for a wide range of unsaturated aldehydes and ,-dicarbonyl reagents. [source] Enantioselective Henry Reactions under Dual Lewis Acid/Amine Catalysis Using Chiral Amino Alcohol Ligands.CHEMINFORM, Issue 42 2005Claudio Palomo Abstract For Abstract see ChemInform Abstract in Full Text. [source] Reductive Intramolecular Henry Reactions Induced by Stryker,s Reagent.CHEMINFORM, Issue 22 2005Wing Ki Chung Abstract For Abstract see ChemInform Abstract in Full Text. [source] Ionic Liquid Catalyzed Henry Reactions.CHEMINFORM, Issue 25 2004Tao Jiang Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthesis and Evaluation of S - and C(1) -Substituted Analogues of LincomycinHELVETICA CHIMICA ACTA, Issue 2 2009Marie-Pierre Collin Abstract New thioglycosides and C(1) -alkylated thioglycosides (S -ulosides) of lincomycin were synthesized, and their antibiotic activities were determined. The S -aryl and S -arylalkyl analogues 11a,11i were obtained by S -glycosylation of the sulfoxides 7 with arenethiols, or by S -alkylation of the thiol 14 with alkyl bromides. Lincomycin derivatives 27, 32a, 32b, 38a, 38b, 44, and 47 were prepared via Henry reaction or Michael addition of the lincosamine-derived 1-deoxy-1-nitropyranoses 22. The S -alkyl derivatives showed a similar activity and specificity as lincomycin. Lipophilic S -uloside analogues were two- to fourfold less active than the parent antibiotic, whilst the hydrophilic analogues were inactive. [source] A Highly Diastereoselective Tertiary Amine-Catalyzed Cascade Michael,Michael,Henry Reaction between Nitromethane, Activated Alkenes and ,,,-Unsaturated Carbonyl CompoundsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1 2010Bo Zhang Abstract A new tertiary amine-catalyzed cascade Michael,Michael,Henry reaction between nitromethane, a doubly activated alkene and an ,,,-unsaturated carbonyl compound is described, which provides a convenient and efficient synthesis for densely functionalized cyclohexanes and some bicyclic compounds in moderate to excellent yields with high diastereoselectivity. [source] ChemInform Abstract: Catalytic Asymmetric Domino Michael,Henry Reaction: Enantioselective Access to Bicycles with Consecutive Quaternary Centers by Using Bifunctional Catalysts.CHEMINFORM, Issue 34 2010Magnus Rueping Abstract A bifunctional, cinchonidine-based, thiourea catalyst is shown to catalyze the enantioselective domino Michael,Henry reaction of cyclohexadienone (I) with various ,-nitrostyrenes. [source] A Highly Effective Bis(sulfonamide),Diamine Ligand: A Unique Chiral Skeleton for the Enantioselective Cu-Catalyzed Henry ReactionCHEMISTRY - A EUROPEAN JOURNAL, Issue 28 2010Wei Jin A skeleton in the closet! As a unique chiral skeleton, the newly developed bis(sulfonamide),diamine, which contains both diamine and bis(sulfonamide) moieties, was a highly effective ligand for the asymmetric Cu(OAc)2 -catalyzed Henry reaction between nitromethane and aldehydes with a low catalyst loading at room temperature (see scheme). Both aliphatic and aromatic aldehydes gave excellent enantioselectivities of up to 99,%,ee. [source] New Highly Asymmetric Henry Reaction Catalyzed by CuII and a C1 -Symmetric Aminopyridine Ligand, and Its Application to the Synthesis of MiconazoleCHEMISTRY - A EUROPEAN JOURNAL, Issue 15 2008Gonzalo Blay Dr. Abstract A new catalytic asymmetric Henry reaction has been developed that uses a C1 -symmetric chiral aminopyridine ligand derived from camphor and picolylamine. A variety of aromatic, heteroaromatic, aliphatic, and unsaturated aldehydes react with nitromethane and other nitroalkanes in the presence of DIPEA (1.0,equiv), Cu(OAc)2,H2O (5,mol,%), and an aminopyridine ligand (5,mol,%) to give the expected products in high yields (up to 99,%), moderate-to-good diastereoselectivites (up to 82:18), and excellent enantioselectivities (up to 98,%). The reaction is air-tolerant and has been used in the synthesis of the antifungal agent miconazole. [source] Rational Design of Sterically and Electronically Easily Tunable Chiral Bisimidazolines and Their Applications in Dual Lewis Acid/Brønsted Base Catalysis for Highly Enantioselective Nitroaldol (Henry) ReactionsCHEMISTRY - A EUROPEAN JOURNAL, Issue 6 2007Kuoyan Ma Abstract A new addition to the rational design of sterically and electrically easily tunable chiral bis(imidazoline) ligands from chiral amino alcohols has been developed. Vast structural variation of chiral bis(imidazoline) ligands can be simply achieved by the choice of both the 1,2-amino alcohol and its N-1 R1 substituent. A small library of chiral bisimidazolines (1,a,h) has been constructed. The method has provided an easy and simplified route to a diverse set of air-stable and water-tolerant chiral bis(imidazoline) ligands on 10,g scales. The dual Lewis Acid/Brønsted base catalytic system generated from the (S)- 1,a/Cu(OTf)2 complex and Et3N was able to catalyze Henry reactions between aldehydes and nitromethane effectively at room temperature, and also to tolerate a wide scope of aldehydes with excellent enantiomeric excesses. Not only aromatic aldehydes but also aliphatic aldehydes afforded the nitroalcohol products, with enantiomeric excesses in the 93,98,% range. This dual catalytic system is among the most effective systems so far reported for the asymmetric parent Henry reactions. This work also represents the first members of the class of chiral bisimidazolines to have been demonstrated to achieve excellent enantioselectivities. [source] | ||||||||||||||||||||||