A new type of pyrrolidine-based organocatalyst, which was developed earlier in our lab, has been found to be very effective for the Michael addition reaction in aqueous solvents involving a wide range of α,β-unsaturated aldehydes and malonate derivatives. For the reactions studied, good to excellent yields (73%-96%) and high to excellent enantioselectivities (up to 97%) were obtained using this...

An efficient approach for the synthesis of 3-substituted-3-hydroxy-2-oxindoles has been achieved via an aldol reaction of α,β-unsaturated ketones and isatins using arginine as an organocatalyst. A range of 3-substituted-3-hydroxy-2-oxindoles were obtained in moderate to high (up to 99%) yields. These 3-substituted-3-hydroxy-2-oxindoles with an additional enone moiety provide an opportunity for ...

A striking breakthrough to the frame of traditional cross-couplings/C-H functionalizations using an organocatalyst remains unprecedented. We uncovered a conceptually different approach toward the biaryl syntheses by using DMEDA as the catalyst to promote the direct C-H arylation of unactivated benzene in the presence of potassium tert-butoxide. The arylation of unactivated benzene with aryl iod...

in this research, (carboxy-3-oxopropylamino)-3-propylsilylcellulose (copapsc) as an organocatalyst, has been synthesized by grafting of succinic anhydride on the nh2-modified cellulose (cellulose functionalized with 3- aminopropyltriethoxysilane). the –co2h group-functionalized cellulose (copapsc) is used as a catalyst for the synthesis of coumarin derivatives from the reaction of phenolic subs...

A series of chiral enantiomerically pure aziridines containing a phosphine moiety were synthesized and successfully applied as organocatalysts in asymmetric intramolecular Rauhut–Currier reactions p-quinone derivatives. The desired phenols achieved high chemical yields with satisfactory values enantiomeric excess (up to 98% ee, some cases). stereochemical course the title reaction may be contro...

The search for viable carbon-neutral sources of renewable energy is one the most critical challenges in science today. chemical community committed to seeking efficient, inexpensive, and sustainable electrocatalysts that can exploit produced by resources. Here, an ethanol organocatalyst, which green cheap, efficiently catalyze oxidation Li2S electrochemical reactions cathodes identified . This ...

Photoredox catalysis and organocatalysis represent two powerful fields of molecule activation that have found widespread application in the areas of inorganic and organic chemistry, respectively. We merged these two catalysis fields to solve problems in asymmetric chemical synthesis. Specifically, the enantioselective intermolecular alpha-alkylation of aldehydes has been accomplished using an i...

1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD) is an effective organocatalyst for acyl transfer as well as the ring-opening polymerization of cyclic esters. Its high activity is attributed to its ability to simultaneously activate both esters and alcohols, as demonstrated in a model reaction. This unique mechanism makes TBD a remarkably simple example of a bifunctional catalyst. The simplicity of th...

A new highly efficient three-component reaction of alkyl acrylate, aldehyde and dialkyl malonate using ethyl diphenylphosphine as organocatalyst has been described. Various highly functional compounds bearing hydroxyl groups and the ester functions can be easily prepared in moderate to good yields according to our one-step procedure. The reactions are believed to proceed via Morita-Baylis-Hillm...

Kinetic studies of a low-molecular weight organocatalyst 1 are presented. Compound 1 contains two histidines and one cationic side chain attached to a central aromatic core. In aqueous solution 1 accelerates the hydrolysis of a prototypal phosphodiester with rate enhancements of up to two orders of magnitude. A detailed HPLC analysis of hydrolysis experiments in Bis-Tris-buffer showed that the ...