65021-67-2

Upstream product

• 108-85-0 1-bromocyclohexane 
• 108-44-1 1-amino-3-methylbenzene 
• 108-93-0 cyclohexanol 
• 108-94-1 cyclohexanone 
• 110-82-7 cyclohexane 
• 99-08-1 1-methyl-3-nitrobenzene 
• 108-91-8 cyclohexylamine 
• 591-24-2 3-Methylcyclohexanone 
• 108-95-2 phenol 
• 110-89-4 piperidine 
• 108-41-8 1-chloro-3-methylbenzene 
• 591-17-3 meta-bromotoluene 
• 625-95-6 3-Iodotoluene 

Downstream Products

• 1451061-05-4 1-cyclohexyl-4-methylindoline-2,3-dione 
• 1451061-07-6 1-cyclohexyl-6-methylindoline-2,3-dione 

Relevant academic research and scientific papers

Visible-light-mediated tungsten-catalyzed C-H amination of unactivated alkanes with nitroarenes

Alkylamines are important motifs in pharmaceutical and material sciences. The existing reports of C-H amination are limited to ammonia, diazo and azide nitrogen sources. This work describes a rapid construction of C-N bonds from accessible nitroarene and alkane feedstock under decatungstate catalysis. A variety of C-H precursors including gaseous, linear, cyclic and benzylic hydrocarbons could adopt this protocol to afford the corresponding alkylamines in high efficiency. [Figure not available: see fulltext.]

In Situ Formation of Cationic π-Allylpalladium Precatalysts in Alcoholic Solvents: Application to C-N Bond Formation

We report an efficient Buchwald-Hartwig cross-coupling reaction in alcoholic solvent, in which a low catalyst loading showed excellent performance for coupling aryl halides (I, Br, and Cl) with a broad set of amines, amides, ureas, and carbamates under mild conditions. Mechanistically speaking, in a protic and polar medium, extremely bulky biarylphosphine ligands interact with the dimeric precatalyst [Pd(π-(R)-allyl)Cl]2 to form the corresponding cationic complexes [Pd(π-(R)-allyl)(L)]Cl in situ and spontaneously. The resulting precatalyst further evolves under basic conditions into the corresponding L-Pd(0) catalyst, which is commonly employed for cross-coupling reactions. This mechanistic study highlights the prominent role of alcoholic solvents for the formation of the active catalyst.

Development of an aryl amination catalyst with broad scope guided by consideration of catalyst stability

We have developed a new dialkylbiaryl monophosphine ligand, GPhos, that supports a palladium catalyst capable of promoting carbon-nitrogen cross-coupling reactions between a variety of primary amines and aryl halides; in many cases, these reactions can be carried out at room temperature. The reaction development was guided by the idea that the productivity of catalysts employing BrettPhos-like ligands is limited by their lack of stability at room temperature. Specifically, it was hypothesized that primary amine and N-heteroaromatic substrates can displace the phosphine ligand, leading to the formation of catalytically dormant palladium complexes that reactivate only upon heating. This notion was supported by the synthesis and kinetic study of a putative off-cycle Pd complex. Consideration of this off-cycle species, together with the identification of substrate classes that are not effectively coupled at room temperature using previous catalysts, led to the design of a new dialkylbiaryl monophosphine ligand. An Ot-Bu substituent was added ortho to the dialkylphosphino group of the ligand framework to improve the stability of the most active catalyst conformer. To offset the increased size of this substituent, we also removed the para i-Pr group of the non-phosphorus-containing ring, which allowed the catalyst to accommodate binding of even very large α-tertiary primary amine nucleophiles. In comparison to previous catalysts, the GPhos-supported catalyst exhibits better reactivity both under ambient conditions and at elevated temperatures. Its use allows for the coupling of a range of amine nucleophiles, including (1) unhindered, (2) five-membered-ring N-heterocycle-containing, and (3) α-tertiary primary amines, each of which previously required a different catalyst to achieve optimal results.

Synthesis of unsymmetrically substituted triarylaminesviaacceptorless dehydrogenative aromatization using a Pd/C andp-toluenesulfonic acid hybrid relay catalyst

An efficient and convenient procedure for synthesizing triarylamines based on a dehydrogenative aromatization strategy has been developed. A hybrid relay catalyst comprising carbon-supported Pd (Pd/C) andp-toluenesulfonic acid (TsOH) was found to be effective for synthesizing a variety of triarylamines bearing different aryl groups starting from arylamines (diarylamines or anilines), using cyclohexanones as the arylation sources under acceptorless conditions with the release of gaseous H2. The proposed reaction comprises the following relay steps: condensation of arylamines and cyclohexanones to produce imines or enamines, dehydrogenative aromatization of the imines or enamines over Pd nanoparticles (NPs), and elimination of H2from the Pd NPs. In this study, an interesting finding was obtained indicating that TsOH may promote the dehydrogenation.

Palladium-catalyzed reductive coupling of nitroarenes with phenols leading to n-cyclohexylanilines

A direct and efficient palladium-catalyzed reductive coupling reaction of nitroarenes with phenols has been developed. A series of Ncyclohexylaniline derivatives was easily and efficiently obtained in moderate to good yields via C-N bond formation by the

Organonickel complexes encumbering bis-imidazolylidene carbene ligands: Synthesis, X-ray structure and catalytic insights on Buchwald-Hartwig amination reactions

New four coordinated homoleptic bis(diimidazolylidene)nickel(II) complexes (C1 & C2) were synthesized and characterized by elemental analysis, NMR (1H and13C) as well as ESI-Mass spectrometry. The molecular structure of the complex C1 was identified by means of single-crystal X-ray diffraction analysis, which revealed that the complexes possess a distorted square planar geometry with chelating bis(diimidazolylidene) NHC ligands and two non coordinating bromide counter ions in tetradentate C4fashion. A survey of their catalytic activity in Buchwald?Hartwig amination has been performed. The newly synthesized complexes also catalyzed the amination of aryl chlorides in the presence of KOtBu. Various aryl chlorides and amines can react smoothly to give the corresponding aminated products in moderate to high yields. The scope of the reaction encompasses electronically varied aryl chlorides and nitrogen-containing heteroaryl chlorides, including pyridine and quinoline derivatives. Both secondary and primary amines are well tolerated under the optimal reaction conditions.

Efficient Biocatalytic Reductive Aminations by Extending the Imine Reductase Toolbox

Chiral secondary and tertiary amines are ubiquitous in pharmaceutical, fine, and specialty chemicals, but their synthesis typically suffers from significant sustainability and selectivity challenges. Biocatalytic alternatives, such as enzyme-catalyzed reductive amination, offer several advantages over traditional chemistry, but industrial applicability has not yet been demonstrated. Herein, we report the use of cell lysates expressing imine reductases operating at 1:1 stoichiometry for a variety of amines and carbonyls. A collection of biocatalysts with diversity in coverage of small molecules and direct industrial applicability is presented.

Facile access to: N -substituted anilines via dehydrogenative aromatization catalysis over supported gold-palladium bimetallic nanoparticles

N-Substituted anilines are widely utilized important compounds, and the development of their diverse synthetic procedures is of great significance. Herein, we have successfully developed a widely applicable powerful catalytic route to N-substituted anilines. In the presence of a gold-palladium alloy nanoparticle catalyst (Au-Pd/Al2O3) and styrene, various kinds of structurally diverse N-substituted anilines (twenty three examples) could be synthesized starting from cyclohexanones and amines (including aliphatic primary and secondary amines and anilines). The catalytic performance was strongly influenced by the nature of the catalyst. A supported gold catalyst (Au/Al2O3) was completely inactive for the present transformation. Although a supported palladium catalyst (Pd/Al2O3) gave the desired N-substituted anilines to some extent, the performance was inferior to that of Au-Pd/Al2O3. The catalytic activity of the palladium species in Au-Pd/Al2O3 was at least ca. three times higher than that in Pd/Al2O3. Moreover, the performance of Au-Pd/Al2O3 was superior to that of a physical mixture of Au/Al2O3 and Pd/Al2O3. Thus, palladium was intrinsically effective for the present transformation (dehydrogenative aromatization) and its performance was improved by alloying with gold. The present transformation proceeds through a sequence of the dehydrative condensation of cyclohexanones and amines to produce enamines (or ketimines), followed by the dehydrogenative aromatization to produce the corresponding N-substituted anilines. In the aromatization step, styrene could act as an effective hydrogen acceptor to selectively produce the desired N-substituted anilines without catalyzing the disproportionation of the enamine intermediates. The observed catalysis using Au-Pd/Al2O3 was truly heterogeneous in nature, and Au-Pd/Al2O3 could be reused.

N-Alkylation of amines with phenols over highly active heterogeneous palladium hydride catalysts

Phenols are directly converted to secondary amines in considerable yield via hydrogenation and amination tandem reaction over Al2O3 supported palladium hydride (PdHx) bi-functional catalyst. Note that this system proceeds efficiently with mild conditions under H2 atmosphere, which was difficult to achieve in previous reports. The catalyst and the mechanism of reaction are both studied. Furthermore, various secondary amines can be formed in good yields under this conversion system.