16035-87-3

Upstream product

• 100-14-1 4-nitrobenzyl chloride 
• 104-94-9 4-methoxy-aniline 
• 1149-23-1 diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate 
• 555-16-8 4-nitrobenzaldehdye 
• 100-42-5 styrene 
• 39963-93-4 (E)-4-methoxy-N-(4-nitrobenzylidene)aniline 
• 762-72-1 allyl-trimethyl-silane 
• 95-54-5 1,2-diamino-benzene 
• 137-07-5 2-amino-benzenethiol 
• 5455-87-8 4-methoxy-N-(4-nitrobenzylidene)aniline 
• 103026-74-0 dimethyl 4-benzyl-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate 
• 401636-52-0 di-tert-butyl 4-benzyl-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate 
• 1539-57-7 diethyl 2,6-dimethyl-4-benzyl-1,4-dihydropyridine-3,5-dicarboxylate 
• 100-13-0 4-nitrostyrene 

Downstream Products

• 3682-75-5 2-(4-methoxyphenyl)-2H-indazole 
• 73402-98-9 6-methoxy-2-(4-nitrophenyl)-4-phenylquinoline 
• 555-16-8 4-nitrobenzaldehdye 

Relevant academic research and scientific papers

Highly selective mono-N-benzylation and amidation of amines with alcohols or carboxylic acids using the Ph2PCl/I2/imidazole reagent system

Chlorodiphenylphosphine, imidazole, and molecular iodine in refluxing dichloromethane are used for the efficient preparation of amides under mild reaction conditions. This reagent system also shows excellent selectivity for mono-N-alkylation of amines with alcohols. In this system, the resulting phosphorus byproduct (diphenylphosphinic acid) is easily removed by extraction using an aqueous basic solution in the workup processes, which avoids the tedious and time-consuming chromatographic methods.

Ruthenium N-Heterocyclic Carbene Complexes for Chemoselective Reduction of Imines and Reductive Amination of Aldehydes and Ketones

Chemoselective reduction of imines to secondary amines is catalyzed efficiently by tethered and untethered, half-sandwich ruthenium N-heterocyclic carbene (NHC) complexes at room temperature. The untethered Ru-NHC complexes are more efficient as catalysts for the reduction of aldimines and ketimines than the tethered complexes. Using the best untethered complex as a catalyst, electronic and steric demands on the reaction was probed using a series of imines. Chemoselectivity of the catalyst towards imine reduction was tested by performing inter and intramolecular competitive reactions in a variety of ways. The catalyst exhibits a very high TON and TOF under anaerobic conditions.

High-Throughput Screening of Reductive Amination Reactions Using Desorption Electrospray Ionization Mass Spectrometry

This study describes the latest generation of a high-throughput screening system that is capable of screening thousands of organic reactions in a single day. This system combines a liquid handling robot with desorption electrospray ionization (DESI) mass spectrometry (MS) for a rapid reaction mixture preparation, accelerated synthesis, and automated MS analysis. A total of 3840 unique reductive amination reactions were screened to demonstrate the throughputs that are capable with the system. Products, byproducts, and intermediates were all monitored in full-scan mass spectra, generating a complete view of the reaction progress. Tandem mass spectrometry experiments were conducted to verify the identity of the products formed. The amine and electrophile reactivity trends represented in the data match what is expected from theory, indicating that the system accurately models the reaction performance. The DESI results correlated well with those generated using more traditional mass spectrometry techniques like liquid chromatography-mass spectrometry, validating the data generated by the system.

Improving C=N bond reductions with (Cyclopentadienone)iron complexes: Scope and limitations

Herein, we broaden the application scope of (cyclo-pentadienone)iron complexes 1 in C=N bond reduction. The catalytic scope of pre-catalyst 1b, which is more active than the “Kn?lker complex” (1a) and other members of its family, has been expanded to the catalytic transfer hydrogenation (CTH) of a wider range of aldimines and ketimines, either pre-isolated or generated in situ. The kinetics of 1b-promoted CTH of ketimine S1 were assessed, showing a pseudo-first order profile, with TOF = 6.07 h–1 at 50 % conversion. Moreover, the chiral complex 1c and its analog 1d were employed in the enantioselective reduction of ketimines and reductive amination of ketones, giving fair to good yields and moderate enantioselectivity.

Iron-Catalyzed Nitrene Transfer Reaction of 4-Hydroxystilbenes with Aryl Azides: Synthesis of Imines via C=C Bond Cleavage

C=C bond breaking to access the C=N bond remains an underdeveloped area. A new protocol for C=C bond cleavage of alkenes under nonoxidative conditions to produce imines via an iron-catalyzed nitrene transfer reaction of 4-hydroxystilbenes with aryl azides is reported. The success of various sequential one-pot reactions reveals that the good compatibility of this method makes it very attractive for synthetic applications. On the basis of experimental observations, a plausible reaction mechanism is also proposed.

Reduction of imines catalysed by NHC substituted group 6 metal carbonyls

The catalytic activity of a series of metal carbonyls [M(CO)6], and the corresponding NHC substituted [M(CO)5(NHC)], (M = Cr, Mo, W) complexes was examined in the reduction of N-benzylideneaniline and acetophenone using silyl hydrides and isopropanol/KOH as reductants. The use of various additives and ultraviolet irradiation to promote the reduction of imines using silyl hydrides as reductants was explored. From a comparison of the reactivity of [Mo(CO)6], [Mo(CO)5(NHC)], and [Mo(CO)4(bis NHC)] it was inferred that electron density on the metal centre plays a key role in the catalysis. Four of the best catalysts were then tested in the reduction of a variety of imines with different electronic and steric properties.

Enantioselective Synthesis of β-Aminotetralins via Chiral Phosphoric Acid-catalyzed Reductive Amination of β-Tetralones

A new protocol for the synthesis of chiral β-aminotetralins has been developed via chiral phosphoric acid-catalyzed asymmetric reductive amination of β-tetralones using a Hantzsch ester as an organic hydride donor. Various chiral β-aminotetralins were obtained in good yields with good to high enantioselectivities. Furthermore, the utility of our new protocol was successfully demonstrated in the enantioselective synthesis of rotigotine. (Figure presented.).

A Highly Efficient Base-Metal Catalyst: Chemoselective Reduction of Imines to Amines Using An Abnormal-NHC-Fe(0) Complex

A base-metal, Fe(0)-catalyzed hydrosilylation of imines to obtain amines is reported here which outperforms its noble-metal congeners with the highest TON of 17000. The catalyst, (aNHC)Fe(CO)4, works under very mild conditions, with extremely low catalyst loading (down to 0.005 mol %), and exhibits excellent chemoselectivity. The facile nature of the imine reduction under mild conditions has been further demonstrated by reducing imines towards expensive commercial amines and biologically important N-alkylated sugars, which are difficult to achieve otherwise. A mechanistic pathway and the source of chemoselectivity for imine hydrosilylation have been proposed on the basis of the well-defined catalyst and isolable intermediates along the catalytic cycle.

CATALYST COMPOUNDS

The present invention relates to an iridium-based catalyst compound for hydrogenating reducible moieties, especially imines and iminiums, the catalyst compounds being defined by the formulas: where ring B is either itself polycyclic, or ring B together with R is polycyclic. The catalysts of the invention are particularly effective in reductive amination procedures 10 which involve the in situ generation of the imine or iminium under reductive hydrogenative conditions.

Metal-free reductive amination of aldehydes for the synthesis of secondary and tertiary amines

Reductive amination of aldehydes to produce secondary amines at room-temperature by in situ generated benzimidazoline is discussed. The bonus of the reaction is the formation of pharmaceutically important benzimidazole as a by-product in good yield, which can be recovered from the reaction mixture by simple filtration. The product, secondary amine, is transformed to tertiary amine in the same pot.