92520-15-5

Upstream product

• 106-48-9 4-chloro-phenol 
• 27298-99-3 (R)-1-(4-chlorophenyl)ethylamine 
• 75-36-5 acetyl chloride 
• 35588-60-4 p-chloro-(R,S)-1-phenylethylamine 
• 622-98-0 4-chloro(ethylbenzene) 
• 208118-80-3 1-(4-chlorophenyl)ethenylacetamide 
• 1333-74-0 hydrogen 
• 92916-02-4 (+/-)-3-(p-chlorophenyl)butan-2-one 
• 76-05-1 trifluoroacetic acid 
• 201230-82-2 carbon monoxide 
• 80-43-3 bis(1-methyl-1-phenylethyl)peroxide 
• 141-78-6 ethyl acetate 
• 108-24-7 acetic anhydride 
• 99-91-2 para-chloroacetophenone 

Relevant academic research and scientific papers

Biocatalytic, Intermolecular C?H Bond Functionalization for the Synthesis of Enantioenriched Amides

Directed evolution of heme proteins has opened access to new-to-nature enzymatic activity that can be harnessed to tackle synthetic challenges. Among these, reactions resulting from active site iron-nitrenoid intermediates present a powerful strategy to forge C?N bonds with high site- and stereoselectivity. Here we report a biocatalytic, intermolecular benzylic C?H amidation reaction operating at mild and scalable conditions. With hydroxamate esters as nitrene precursors, feedstock aromatic compounds can be converted to chiral amides with excellent enantioselectivity (up to >99 % ee) and high yields (up to 87 %). Kinetic and computational analysis of the enzymatic reaction reveals rate-determining nitrenoid formation followed by stepwise hydrogen atom transfer-mediated C?H functionalization.

Diaza-Crown Ether-Bridged Chiral Diphosphoramidite Ligands: Synthesis and Applications in Asymmetric Catalysis

A small library of diaza-crown ether-bridged chiral diphosphoramidite ligands was prepared. In the rhodium-catalyzed asymmetric hydrogenation and hydroformylation reactions, these ligands exhibited distinct properties in catalytic activity and/or enantioselectivity. Hydrogenated products with opposite absolute configurations could be obtained in high yields with excellent ee values by utilizing (S,S)-L1 and (S,S)-L3, respectively. Meanwhile, the addition of alkali metal cations caused variations in catalytic outcomes, showing the supramolecular tunability of these Rh/diphosphoramidite catalytic systems.

Development of robust heterogeneous chiral rhodium catalysts utilizing acid?base and electrostatic interactions for efficient continuous-flow asymmetric hydrogenations

Heterogeneous chiral Rh catalysts based on acid?base and electrostatic interactions have been developed. The robust catalysts demonstrate high activity and selectivity in the continuous-flow asymmetric hydrogenation of a wide variety of enamides and dehyd

New chiral ferrocene/indole-based diphosphine ligands for Rh-catalyzed asymmetric hydrogenation of functionalized olefins

Convenient synthesis of a new family of chiral ferrocene/indole-based diphosphine ligands, (Rc,Rp)-IndoFerroPhos (L), from (Sc,Rp)-PPFA and 2-(diphenylphosphino)indole has been described. These new ligands exhibited high efficiency in the Rh-catalyzed asymmetric hydrogenation of functionalized olefins including α-dehydroamino acid esters, α-enamides and dimethyl itaconate, in which up to >99% yield and 98% ee were achieved.

The enzymatic resolution of 1-(4-chlorophenyl)ethylamine by Novozym 435 to prepare a novel triazolopyrimidine herbicide

The kinetic resolution of (R,S)-1-(4-chlorophenyl)ethylamine was accomplished using a commercial lipase from Candida antarctica (Novozym 435). The performance of this lipase was investigated for the enantioselective amidation of (R,S)-1-(4-chlorophenyl)ethylamine, leaving the target product (S)-1-(4-chlorophenyl)ethylamine in its unreacted form. The effects of various types of solvents and an acyl donor, the molar ratio of the substrate to the acyl donor, and the reaction temperature were studied. The optimum reaction conditions were found to result in amidation with methyl 2-tetrahydrofuroate at 40°C in methyl tert-butyl ether, with a substrate/acyl donor molar ratio of 1:2.4. The conversion rate of (R,S)-1-(4-chlorophenyl)ethylamine was 52%, with an enantiomeric excess of 99% towards the unreacted substrate in a reaction time of 22?hours. Finally, using optically pure (S)-1-(4-chlorophenyl)ethylamine as the raw material, the chemical synthesis of (S)-N-(1-(4-chlorphenyl)ethyl)-2-(5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidin-2-ylthio)acetamide, a novel triazolopyrimidine herbicide, was achieved, and the total yield and purity were 83.5% and 95.3%, respectively.

Manganese-Catalyzed Direct Conversion of Ester to Amide with Liberation of H2

A simple and efficient Mn-catalyzed acylation of amines is achieved using both acyl and alkoxy functions of unactivated esters with the liberation of molecular hydrogen as a sole byproduct. The present protocol provides an atom-economical and sustainable route for the synthesis of amides from esters by employing an earth-abundant manganese salt and inexpensive phosphine-free tridentate ligand.

Asymmetric Synthesis of Chiral Primary Amines by Ruthenium-Catalyzed Direct Reductive Amination of Alkyl Aryl Ketones with Ammonium Salts and Molecular H2

A ruthenium/C3-TunePhos catalytic system has been identified for highly efficient direct reductive amination of simple ketones. The strategy makes use of ammonium acetate as the amine source and H2 as the reductant and is a user-friendly and operatively simple access to industrially relevant primary amines. Excellent enantiocontrol (>90% ee for most cases) was achieved with a wide range of alkyl aryl ketones. The practicability of this methodology has been highlighted by scalable synthesis of key intermediates of three drug molecules. Moreover, an improved synthetic route to the optimal diphosphine ligand C3-TunePhos is also presented.

Asymmetric Allylic Alkylation and Hydrogenation with Transition Metal Complexes of Diphosphite Ligands Based on (1S,2S)-Trans-1,2-cyclohexanediol

Abstract: The preparation of new palladium complexes in situ that were composed of a series of chiral diphosphite ligands, which were derived from (1S,2S)-trans-1,2-cyclohexanediol, have been described. It was found that (1S,2S)-bis[(S)-1,1′-binaphthyl-2,

An unexpected copper-catalyzed carbonylative acetylation of amines

A novel copper-catalyzed carbonylative acetylation of amines has been developed. With peroxide as the oxidant as well as the methyl source with a copper catalyst under CO pressure, good yields of N-acetyl amides could be obtained. Notably, this is the first example of carbonylative acetylation.

Amine dehydrogenases: Efficient biocatalysts for the reductive amination of carbonyl compounds

Amines constitute the major targets for the production of a plethora of chemical compounds that have applications in the pharmaceutical, agrochemical and bulk chemical industries. However, the asymmetric synthesis of α-chiral amines with elevated catalytic efficiency and atom economy is still a very challenging synthetic problem. Here, we investigated the biocatalytic reductive amination of carbonyl compounds employing a rising class of enzymes for amine synthesis: amine dehydrogenases (AmDHs). The three AmDHs from this study-operating in tandem with a formate dehydrogenase from Candida boidinii (Cb-FDH) for the recycling of the nicotinamide coenzyme-performed the efficient amination of a range of diverse aromatic and aliphatic ketones and aldehydes with up to quantitative conversion and elevated turnover numbers (TONs). Moreover, the reductive amination of prochiral ketones proceeded with perfect stereoselectivity, always affording the (R)-configured amines with more than 99% enantiomeric excess. The most suitable amine dehydrogenase, the optimised catalyst loading and the required reaction time were determined for each substrate. The biocatalytic reductive amination with this dual-enzyme system (AmDH-Cb-FDH) possesses elevated atom efficiency as it utilizes the ammonium formate buffer as the source of both nitrogen and reducing equivalents. Inorganic carbonate is the sole by-product.