14429-03-9

Upstream product

• 637-69-4 4-Methoxystyrene 
• 100-46-9 benzylamine 
• 100-06-1 1-(4-methoxyphenyl)ethanone 
• 2393-23-9 4-methoxy-benzylamine 
• 98-86-2 acetophenone 
• 14429-17-5 anti-N-(α-methyl-4-methoxybenzylidene)benzylamine 
• 14429-17-5 N-(α-methyl-4-methoxybenzylidene)benzylamine 
• 100-52-7 benzaldehyde 
• 6298-96-0 1(R)-(4-methoxyphenyl)-ethylamine 
• 170222-00-1 (S)-1-(4-methoxyphenyl)ethyl-1,3,2-benzodioxaborole 
• 29237-95-4 chloro-benzyl amine 

Downstream Products

• 900518-21-0 tert-butyl (2R,3R,αR)-2-tert-butylthio-3-[N-(α-methyl-p-methoxybenzyl)amino]-3-phenylpropanoate 
• 1169755-20-7 tert-butyl (3S,4S,5R,αR)-3-[N-benzyl-N-(α-methyl-4'-methoxybenzyl)amino]-4,5-O-isopropylidene-hept-6-enoate 
• 900518-20-9 tert-butyl (2R,3R,αR)-2-tert-butylthio-3-[N-benzyl-N-(α-methyl-p-methoxybenzyl)amino]-3-phenylpropanoate 
• 566930-76-5 N-benzyl-4-methoxy-N-[1-(4-methoxy-phenyl)-ethyl]-benzamide 
• 495380-52-4 (3S,αR)-tert-butyl 3-(4-pyridyl)-3-(N-benzyl-N-4-methoxy-α-methylbenzylamino)propanoate 
• 495380-50-2 (3S,αR)-tert-butyl 3-(N-benzyl-N-α-methyl-4-methoxybenzylamino)-3-(3-pyridyl)propanoate 
• 447416-67-3 tert-butyl (3S,αR)-3-(3,4-difluorophenyl)-3-(N-benzyl-N-α-methyl-4-methoxybenzylamino)propanoate 
• 447416-07-1 tert-butyl (3S,αR)-3-(2-bromophenyl)-3-(N-benzyl-N-α-methyl-4-methoxybenzylamino)propanoate 

Relevant academic research and scientific papers

Chiral cyclometalated iridium complexes for asymmetric reduction reactions

A series of chiral cyclometalated iridium complexes have been synthesised by cyclometalating chiral 2-aryl-oxazoline and imidazoline ligands with [Cp?IrCl2]2. These iridacycles were studied for asymmetric transfer hydrogenation reactions with formic acid as the hydrogen source and were found to display various activities and enantioselectivities, with the most effective ones affording up to 63% ee in the asymmetric reductive amination of ketones and 77% ee in the reduction of pyridinium ions. This journal is

Protic additives or impurities promote imine reduction with pinacolborane

We report here that addition of stoichiometric amounts of alcohols or water to mixtures of imines and pinacolborane promote reduction reactions. The reactions of several imines were examined, revealing that alkyl imines were reduced, while aniline derived imines were not effectively reduced. The use of binol as an additive resulted in modest enantioinduction, however other chiral additives that were screened gave negligible enantioinduction. While the reactions described herein are not competitive in conversion with established imine reduction technologies, this work reveals that the presence of protic impurities must be considered as a promoter of side reactions in catalyzed imine hydroborations. Amines also promote imine reduction in certain cases, raising the possibility of a slow autocatalytic reaction. The ability of water or other protic impurities to promote the reduction of imines with pinacolborane represents an important identification of a potential source of background reaction in catalyzed reductions of imines.

CHIRAL CATALYST AND METHOD FOR ASYMMETRIC REDUCTION OF AN IMINE

The present disclosure discusses (i) a compound having a chemical formula according to Formula (I), or its enantiomer; and (ii) a compound that is reactive with a hydride to produce a compound having a chemical formula according to Formula (I), or its enantiomer. Formula (I) is: Formula (I) where R1 and R2 are H, optionally substituted C1-C3 alkyl, or linked together to form an optionally substituted C3 or C4 alkyl group; R3 and R3' are H; R4 and R4' are the same, and are optionally substituted C1-C6 alkyl; and R5 and R5' are the same, and are optionally substituted aryl or heteroaryl. In some examples, R4 and R5 are linked, and R4' and R5' are linked, where both linking groups are the same. The present disclosure also discusses methods of asymmetric reduction of an imine, and methods of forming the catalysts and pre-catalysts.

Enantioselective Imine Reduction Catalyzed by Phosphenium Ions

The first use of phosphenium cations in asymmetric catalysis is reported. A diazaphosphenium triflate, prepared in two or three steps on a multigram scale from commercially available materials, catalyzes the hydroboration or hydrosilylation of cyclic imin

Hydroboration Catalyzed by 1,2,4,3-Triazaphospholenes

The synthesis and study of the catalytic activity of 1,2,4,3-triazaphospholenes (TAPs) is reported. TAPs represent a more modular scaffold than previously reported diazaphospholenes. TAP halides were shown to catalyze the 1,2 hydroboration of 19 imines, and three α,β unsaturated aldehydes with pinacolborane, including examples that did not undergo hydroboration by previously reported diazaphospholene systems. DFT calculations support a mechanism where a triazaphospholene cation interacts with the substrate, a mechanism distinct from diazaphospholene catalyzed hydroborations.

Asymmetric Imine Hydroboration Catalyzed by Chiral Diazaphospholenes

The first use of diazaphospholenes as chiral catalysts has been demonstrated with enantioselective imine hydroboration. A chiral diazaphospholene prepared in a simple three-step synthesis from commercial materials has been shown to achieve the highest enantioselectivity for the hydroboration of alkyl imines with pinacolborane reported to date. Enantiomer ratios of up to 88:12 were obtained with low (2 mol %) catalyst loadings. Twenty examples of asymmetric reduction employing this main-group catalysis protocol, including the synthesis of the pharmaceuticals ent-rasagiline and fendiline, are shown.

Iron-catalyzed transfer hydrogenation of imines assisted by an iron-based Lewis acid

An iron-catalyzed transfer hydrogenation of N-aryl and N-alkyl imines using isopropanol as the hydrogen donor is reported for the first time. A combination of two iron complexes serving different roles is the key for the success of this catalytic system. As a result, an environmentally friendly and precious metal-free transfer hydrogenation of imines has been developed. The use of a suitable co-catalyst as an activator not only led to efficient transfer hydrogenation, but also showed potential in enantioselective transformation.

Asymmetric Transfer Hydrogenation of Imines using Alcohol: Efficiency and Selectivity are Influenced by the Hydrogen Donor

The influence of the alcohol, as the hydrogen donor, on the efficiency and selectivity of the asymmetric transfer hydrogenation (ATH) of imines is reported for the first time. This discovery not only leads to a highly enantioselective access to N-aryl and N-alkyl amines, but also provides new insight into the mechanism of the ATH of imines. Both experimental and computational studies provide support for the reaction pathway involving an iridium alkoxide as the reducing species.

A highly active cyclometallated iridium catalyst for the hydrogenation of imines

A cyclometallated iridium complex containing an imino ligand has been shown to catalyse the hydrogenation of imines. The catalyst is highly active and selective for imino bonds, with a wide variety of imines being hydrogenated in less than 1 hour at a substrate/catalyst (S/C) ratio of 2000 at 20 bar H 2 pressure and 75 °C.

Asymmetric organocatalytic reduction of ketimines with catecholborane employing a N-triflyl phosphoramide Br?nsted acid as catalyst

The first asymmetric reduction of ketimines with catecholborane employing an enantiopure N-triflyl phosphoramide as the organocatalyst has been developed. Five mole % of the catalyst provides the corresponding secondary amines in very good to almost quantitative yields and good enantioselectivities up to 86:14 e.r. under mild reaction conditions.