Novel catalyst-controlled divergent intramolecular reactions of N-sulfonyl-1,2,3-triazoles with tethered-allylic alcohol have been developed. In the presence of the Pd(0) catalyst alone, 1-vinylated 1,4-dihydroisoquinolin-3-ones were formed, whereas 3-vinylated 2-aminoindanones were accessed under tandem, one-pot, Rh(ii)/Pd(0) dual catalytic conditions. Based on deuterium-labelling experiments and isolation of the intermediate, a plausible reaction mechanism has been proposed.
In industry, the two important nitrile starting materials, adiponitrile and 2-methylglutaronitrile, are primarily manufactured through the well-known DuPont process, which consists of a tandem sequence including first hydrocyanation, isomerization and second hydrocyanation. However, this mature process has the intrinsic defects of step efficiency and regioselectivity. Herein, we report a nickel-catalyzed divergent, one-step double hydrocyanation of 1,3-butadiene to produce either adiponitrile or 2-methylglutaronitrile in high regioselectivity.
Yunnan Key Laboratory of Modern Separation Analysis and Substance Transformation, College of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming Yunnan Province 650500, P. R. China.
Visible light-promoted α-aminoalkyl radical-triggered α-aminoalkylation and α-diaminoalkylation of Morita-Baylis-Hillman acetates with -methyl arylamines to synthesize -containing alkyl acrylates and γ,γ-diaminobutyl esters was reported. Photoinduced α-aminoalkylation is carried out with Na-eosin Y as an organophotocatalyst at room temperature under metal- and oxidant-free conditions. In particular, the α-diaminoalkylation is performed via α-aminoalkyl radical addition/elimination followed by a catalyst-controlled selective α-aminoalkyl radical addition strategy in one step under the [Ir(dtbbpy)(bpy))]PF/KF catalytic system.
Carbohydrates play important roles in medicinal chemistry and biochemistry. However, their synthesis relies on specially designed glycosyl donors, which are often unstable and require multi-step synthesis. Furthermore, the catalytic and stereoselective installation of arylated quaternary stereocentres on sugar rings remains a formidable challenge.
Bridged bicyclic scaffolds are emerging bioisosteres of planar aromatic rings under the concept of "escape from flatland". However, adopting this concept into the exploration of bioisosteres of pyridines remains elusive due to the challenge of incorporating a N atom into such bridged bicyclic structures. Herein, we report practical routes for the divergent synthesis of 2- and 3-azabicyclo[3.
Herein, we report the synthesis of 2-chromenes via catalyst-controlled highly regioselective [3 + 3] annulation of vinyl sulfoxonium ylides with quinones. Under boron-catalyzed conditions, the reaction between the ylide and quinone resulted in the formation of 2-chromene-4-carboxylates. In contrast, a different mechanistic pathway was observed when utilizing a Ru(II) catalytic system, which led to the formation of 2-chromene-2-carboxylates through a furan intermediate.
