The first direct asymmetricvinylogousMannich (AVM) reaction of alpha,alpha-dicyanoolefins and N-Boc aldimines was described promoted by a simple chiral bifunctional thiourea-tertairy amine organocatalyst. The reaction was highlyefficient (S/C up to 1000) and regio-, stereoselective (generally >99% de, 96 to >99.5% ee) at room temperature for a broad array of substrates. Enantiomerically pure delta-amino
Synthesis of Polyfunctionalized Pyrroles via a Tandem Reaction of Michael Addition and Intramolecular Cyanide-Mediated Nitrile-to-Nitrile Condensation
作者:Sankar K. Guchhait、Shailendra Sisodiya、Meenu Saini、Yesha V. Shah、Gulshan Kumar、Divine P Daniel、Neha Hura、Vikas Chaudhary
DOI:10.1021/acs.joc.8b00465
日期:2018.5.18
A new approach for the synthesis of tetrasubstituted/functionalized NH-pyrroles from gem-diactivated acrylonitriles and TMSCN has been developed. The strategy utilizes the generation of vic-dinitrile viaMichaeladdition and cyanide-mediated nitrile-to-nitrile cyclocondensation, which proceed in tandem guided by manifold roles of “CN”. An extended application to the production of fused pyrrole has
A Simple, Efficient and Green Procedure for Knoevenagel Condensation in Water or under Solvent-free Conditions
作者:Ya-Qin Yu、Zhong-Liang Wang
DOI:10.1002/jccs.201200391
日期:2013.3
1,4‐Diazabicyclo[2.2.2]octane was used as an efficient catalyst in the Knoevenagelcondensation reaction of various kinds of aromatic/aliphatic/heterocyclic/αβ‐unsaturated aldehydes and ketones with active methylene compounds. This is a convenient and rapid method for Knoevenagelcondensation, which affords the corresponding substituted electrophilic alkenes in excellent yields. The reaction condition
Knöevenagelreactions of aldehydes and ketones with malononitrile, isopropyl cyanoacetate and diisopropyl malonate catalyzed by Ti(O-i-Pr)4 proceeded smoothly in i-PrOH to give the corresponding reaction products in good to high yield. 3-Substituted coumarins were prepared by the present method.
Betti base-modified magnetic nanoparticles as a novel basic nanocatalyst in Knoevenagel condensation and its related palladium nanocatalyst in Suzuki coupling reactions
作者:Payam Heidari、Ramin Cheraghali、Hojat Veisi
DOI:10.1002/aoc.3532
日期:2016.12
Betti base‐modified Fe3O4 nanoparticles have been successfully designed and synthesized for the first time through the condensation of Fe3O4 magneticnanoparticles coated by (3‐aminopropyl)triethoxysilane with β‐naphthol and benzaldehyde. Their application as a novel magnetic nanocatalyst in the Knoevenagel condensation and also application to immobilization of palladiumnanoparticles for Suzuki coupling