Michael Addition of Amines to Activated Alkenes Promoted by Zn/NH_4Cl System

A Zn/NH4Cl system was exploited at room temperature to promote the Michael addition reaction of various primary and secondary amines with α,β-unsaturated esters,nitriles,amides,and ketones to give the corresponding saturated amines under the mild condition in high yield.

Asymmetric Baylis-Hillman Reaction between Chiral Activated Alkenes and Aromatic Aldehydes in Me_(3)N/H_(2)O/Solvent Medium

Chiral activated alkene, L-menthyl acrylate and （＋）-N-α-phenylethyl acrylamide, induced asymmetric Baylis-HiUman reaction of aromatic aldehydes was realized at 25℃ for 7 days in Me3N/H2O/solvent homogeneous medium. The corresponding Baylis-Hillman adducts were obtained in good chemical yield with moderate to excellent diastereoselectivity （up to 99% de）.

Theoretical Investigation of the Mechanism of Rh(III)-catalyzed Annulation of 2-Biphenylboronic Acid with Activated Alkene

The mechanism is investigated for Cp^(tBu)Rh(OH)_(2)-catalyzed annulation of 2-biphenylboronic acid with three activated alkenes using M06-2X functional.The reaction comprises transmetalation via two steps and following C-H activation producing reactive Rh-biphenyl complex with two Rh—Cσbonds.After the coordination/insertion of alkenes,respective fused or bridged cyclic products are yielded depending on different alkenes accompanied by the release of CptBuRh.The promotion of Cp^(tBu)Rh(OH)_(2) lies in the barrier decrease of transmetalation and C-H activation ready for coordination/insertion ensuring the smooth progress of common rate-limiting reductive elimination.The stereoselective transfer and ring rotation are specific for benzoquinone and cyclopropenone.The role of Rh(III)catalyst and release of Rh(I)is supported by Multiwfn analysis on frontier molecular orbital(FMO)of specific transiton states(TSs)and Mayer bond order(MBO)value of vital bonding,breaking.

Electrochemical Carboarylation of Activated Alkenes with CO_(2)and Electron-deficient Aryl Bromides

Comprehensive Summary The simultaneous construction of two vicinal C—C bonds in a molecule remains a significant challenge.In this work,we disclose an electroreductive carboarylation of activated alkenes under mild,transition metal-free conditions.Utilizing readily available starting materials(electron-deficient aryl bromides,activated alkenes,and CO_(2)),this method demonstrates broad substrate scope and good functional group tolerance.Notably,this strategy enables the addition of two distinct electrophiles across an alkene in a highly chemo-and regioselective manner.

An expeditious synthesis of isoxazoline using cetyltrimethylammonium cerium nitrate:A phase transferring oxidative 1,3-dipolar cycloaddition

An expeditious and effective method for synthesis of isoxazoline from aldoximes and activated alkenes using cetyltrimethylammonium cerium nitrate at room temperature is described.Reaction was completed within short time period in high yields at room temperature.

AgF-Mediated Dialkylation of Activate Alkenes: An Efficient Access to Nitrile-Containing Spirooxindoles

A novel Ag-mediated dialkylation reaction of alkenes was disclosed,in which AgF was essential to activate C-H bond of acetonitrile.This reaction provided an efficient way to nitrile-containing spirooxindoles from readily available(1H-indol-3-yl)methanamine derivatives.