53603-13-7Relevant academic research and scientific papers
Blue Light-Promoted N?H Insertion of Carbazoles, Pyrazoles and 1,2,3-Triazoles into Aryldiazoacetates
Stivanin, Mateus L.,Fernandes, Alessandra A. G.,da Silva, Amanda F.,Okada, Celso Y.,Jurberg, Igor D.
, p. 1106 - 1111 (2020/01/25)
Blue light irradiation of aryldiazoacetates leads to the formation of free carbenes, which can react with carbazoles, pyrazoles and 1,2,3-triazoles to afford the corresponding N?H inserted products. These reactions are performed under air and at room temperature, allowing the mild preparation of a variety of motifs found in biologically relevant targets. (Figure presented.).
Chemo- and Enantioselective Pd/B Hybrid Catalysis for the Construction of Acyclic Quaternary Carbons: Migratory Allylation of O-Allyl Esters to α- C-Allyl Carboxylic Acids
Fujita, Taiki,Yamamoto, Tomohiro,Morita, Yuya,Chen, Hongyu,Shimizu, Yohei,Kanai, Motomu
supporting information, p. 5899 - 5903 (2018/05/14)
We describe herein the asymmetric synthesis of α-allyl carboxylic acids containing an α-quaternary stereocenter by a chiral hybrid catalyst system comprising palladium and boron complexes. The reaction proceeded through palladium-catalyzed ionization of α,α-disubstituted O-allyl esters for the generation of chiral π-allyl palladium complex as an electrophile, boron-catalyzed enolization of the carboxylate part for the generation of chiral α,α-disubstituted carboxylic acid-derived enolates as a nucleophile, and enantioselective coupling between the thus-generated nucleophile and electrophile. Proper combinations of chiral ligands for the boron and palladium catalysts were crucial. The reaction proceeded chemoselectively at the α-position of the carboxylic acid group.
Dual Bronsted acid/nucleophilic activation of carbonylimidazole derivatives
Heller, Stephen T.,Fu, Tingting,Sarpong, Richmond
supporting information; experimental part, p. 1970 - 1973 (2012/06/01)
Carbonylimidazole derivatives have been found to be highly active acylation reagents for esterification and amidation in the presence of pyridinium salts. These reactions are thought to involve both Bronsted acid and nucleophilic catalysis. This mode of activation has been applied to the synthesis of difficult to access oxazolidinones, as well as esters and amides. Finally, the use of pyridinium salts has been shown to accelerate the esterification of carboxylic acids with imidazole carbamates.
On the reactivity of imidazole carbamates and ureas and their use as esterification and amidation reagents
Heller, Stephen T.,Sarpong, Richmond
experimental part, p. 8851 - 8859 (2011/12/02)
The optimization, substrate scope, and mechanism of esterification and amidation of carboxylic acids mediated by imidazole-based reagents are discussed. The innate reactivity of carbonylimidazole reagents with a range of nucleophiles is also explored. New reagents developed for the synthesis of α,β-unsaturated esters are described, as are reagents for the preparation of tertiary amides directly from carboxylic acids.
