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• 877-42-9 6-Bromo-2-methyl-quinoline 

Relevant academic research and scientific papers

Iridium-catalyzed asymmetric hydrogenation of quinoline derivatives with C3*-tunephos

A series of C3-TunePhos chiral diphosphine ligands has been successfully applied in the iridium-catalyzed enantioselective hydrogenation of quinolines, and this methodology provided an efficient access to a variety of optically active tetrahydroquinolines with up to 93% ee. Furthermore, attempts on the asymmetric hydrogenation of quinoline N-oxide are also discussed.

Efficient Asymmetric Hydrogenation of Quinolines over Chiral Porous Polymers Integrated with Substrate Activation Sites

Heterogeneous asymmetric hydrogenation of quinolines for the production of optically active tetrahydroquinoline derivatives still remains a difficult task due to the aromatic stability of quinolines. Herein, we reported efficient heterogeneous asymmetric hydrogenation of quinolines over chiral porous polymers integrated with both chiral active sites (VDPEN-RuOTs) and substrate activation sites (TsOH). The porous polymer integrated with TsOH is 10 times more active than that without TsOH in the asymmetric hydrogenation of 2-methylquinoline. The volcano curve of TOF with the TsOH/Ru ratio confirms the synergistic catalysis of VDPEN-RuOTs and TsOH. Comparison results with a homogeneous catalytic system imply that the synergy between chiral centers and acidic sites is greatly enhanced in the polymer network. Under optimized conditions, the chiral porous polymer afforded up to 90% ee with 90 h-1 TOF, which is one of the best solid catalysts for asymmetric hydrogenation of quinoline derivatives ever reported. Furthermore, the bifunctional porous polymers realized the asymmetric cascade hydrogenation/reductive amination reaction to obtain benzo-quinolizidines. Our primary results suggest that the incorporation of substrate activation sites near chiral centers is an efficient strategy for the synthesis of high-performance solid catalysts for heterogeneous asymmetric catalysis.

Manganese-Catalyzed Asymmetric Hydrogenation of Quinolines Enabled by π–π Interaction**

The non-noble metal-catalyzed asymmetric hydrogenation of N-heteroaromatics, quinolines, is reported. A new chiral pincer manganese catalyst showed outstanding catalytic activity in the asymmetric hydrogenation of quinolines, affording high yields and enantioselectivities (up to 97 % ee). A turnover number of 3840 was reached at a low catalyst loading (S/C=4000), which is competitive with the activity of most effective noble metal catalysts for this reaction. The precise regulation of the enantioselectivity were ensured by a π–π interaction.

New class of P-stereogenic chiral Br?nsted acid catalysts derived from chiral phosphinamides

A new class of N–H Br?nsted acid organocatalysts that feature P-stereogenic chirality was developed. These catalysts were prepared from P-stereogenic chiral phosphinamides and show similar reactivity to BINOL derived phosphoric acid toward the reduction of quinolines via transfer hydrogenation. It shows that stereoselectivity is induced by the P-chiral environment that is created by the substituents attached to the phosphorous atom, which can be readily tuned and modified.

P -Chiral, N -phosphoryl sulfonamide Br?nsted acids with an intramolecular hydrogen bond interaction that modulates organocatalysis

Br?nsted acids exemplified by OttoPhosa I (5c) were designed and evaluated in the asymmetric transfer hydrogenation of quinolines. Their catalytic properties are modulated by an intramolecular hydrogen bond that rigidifies their catalytic cavity, accelerates the reaction rate and improves enantioselectivity.

Bronsted acid differentiated metal catalysis by kinetic discrimination

A Bronsted acid differentiated metal catalyzed hydrogenation has been developed. A combinatorial variation of chiral triflylamides with achiral metal complexes results in a highly active catalyst for the asymmetric reduction.