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• 108-91-8 cyclohexylamine 
• 123-11-5 4-methoxy-benzaldehyde 
• 201230-82-2 carbon monoxide 
• 696-62-8 para-iodoanisole 
• 105-13-5 4-Methoxybenzyl alcohol 
• 33739-91-2 N-cyclohexyl-4-methoxybenzamide 
• 2393-23-9 4-methoxy-benzylamine 
• 63674-11-3 N-[(4-methoxyphenyl)methyl]cyclohexanamine 

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• 3380-73-2 1-(4-methoxyphenyl)-1,2,3,4-tetrahydro-1H-pyrido[3,4-b]indole 
• 1749-08-2 N-(4-methoxy benzylidene)-4-methoxyaniline 
• 14429-14-2 N-(4-methoxybenzyl)-4-methoxyaniline 
• 176696-41-6 2-Cyclohexyl-3-(4-methoxy-phenyl)-[1,2]thiazetidine 1,1-dioxide 
• 1624-46-0 (E)-1,N-bis(4-methoxyphenyl)methanimine 
• 3526-43-0 N-(4-methoxybenzyl)aniline 
• 836-41-9 p-methoxybenzylidene-phenylamine 
• 108-91-8 cyclohexylamine 

Relevant academic research and scientific papers

Vanadium-and chromium-catalyzed dehydrogenative synthesis of imines from alcohols and amines

Vanadium(IV) tetraphenylporphyrin dichloride and chromium(III) tetraphenylporphyrin chloride have been developed as catalysts for the acceptorless dehydrogenation of alcohols. The catalysts have been applied to the direct synthesis of imines in overall good yields from a variety of alcohols and amines. The transformations are proposed to proceed by metal?ligand bifunctional pathways with an outer-sphere transfer of two hydrogen atoms from the alcohol to the metal porphyrin complexes. The results show that vanadium and chromium catalysts can also be employed for the dehydrogenation of alcohols with the release of hydrogen gas, and they may represent valuable alternatives to other catalysts based on Earth-abundant metals.

Silicon hydrogenation reaction method of organic boron and inorganic alkali catalysis amide (by machine translation)

The method is characterized in that organic boron and inorganic bases are used as catalysts, silane is used as a reducing agent, primary amide is reduced to primary amine or dehydration dinitrile, the secondary amide is reduced to a secondary amine or aldimine, and the tertiary amide is reduced to tertiary amine. The method has the advantages of simple operation, mild reaction conditions, wide substrate universality, good functional group compatibility and the like, and has the characteristics of good stability, cheap and accessible catalyst, simple and convenient operation, high practicality and the like. (by machine translation)

H2 Activation by Non-Transition-Metal Systems: Hydrogenation of Aldimines and Ketimines with LiN(SiMe3)2

In recent years, H2 activation at non-transition-metal centers has met with increasing attention. Here, a system in which H2 is activated and transferred to aldimines and ketimines using substoichiometric amounts of lithium bis(trimethylsilyl)amide is reported. Notably, the reaction tolerates the presence of acidic protons in the α-position. Mechanistic investigations indicated that the reaction proceeds via a lithium hydride intermediate as the actual reductant.

A BEt3-Base catalyst for amide reduction with silane

Reported herein is the development of a simple but practical catalytic system for the selective reduction of amides with hydrosilane or hydrosiloxane. Low-cost and readily available triethylborane (1.0 M in THF), in combination with a catalytic amount of an alkali metal base, was found to catalyze the reduction of all three amide classes (tertiary, secondary, and primary amides) to form amines under mild conditions. In addition, the selective transformation of secondary amides to aldimines and primary amides to nitriles can also be achieved by using a proper combination of BEt3 and base. The scope of these BEt3-base-catalyzed amide hydrosilylation reactions has been explored in depth. Preliminary results of mechanistic studies suggest a modified Piers' silane Si-H···B activation mode wherein the hydride abstraction by BEt3 is promoted by the coordination of an alkoxide or hydroxide anion to the Si center.

A BEt3-Base Catalyst for Amide Reduction with Silane

Reported herein is the development of a simple but practical catalytic system for the selective reduction of amides with hydrosilane or hydrosiloxane. Low-cost and readily available triethylborane (1.0 M in THF), in combination with a catalytic amount of an alkali metal base, was found to catalyze the reduction of all three amide classes (tertiary, secondary, and primary amides) to form amines under mild conditions. In addition, the selective transformation of secondary amides to aldimines and primary amides to nitriles can also be achieved by using a proper combination of BEt3 and base. The scope of these BEt3-base-catalyzed amide hydrosilylation reactions has been explored in depth. Preliminary results of mechanistic studies suggest a modified Piers' silane Si-H···B activation mode wherein the hydride abstraction by BEt3 is promoted by the coordination of an alkoxide or hydroxide anion to the Si center.

Manganese(III) Porphyrin-Catalyzed Dehydrogenation of Alcohols to form Imines, Tertiary Amines and Quinolines

Manganese(III) porphyrin chloride complexes have been developed for the first time as catalysts for the acceptorless dehydrogenative coupling of alcohols and amines. The reaction has been applied to the direct synthesis of imines, tertiary amines and quinolines where only hydrogen gas and/or water are formed as the by-product(s). The mechanism is believed to involve the formation of a manganese(III) alkoxide complex which degrades into the aldehyde and a manganese(III) hydride species. The latter reacts with the alcohol to form hydrogen gas and thereby regenerates the alkoxide complex.

Development and mechanistic investigation of the manganese(iii) salen-catalyzed dehydrogenation of alcohols

The first example of a manganese(iii) catalyst for the acceptorless dehydrogenation of alcohols is presented. N,N′-Bis(salicylidene)-1,2-cyclohexanediaminomanganese(iii) chloride (2) has been shown to catalyze the direct synthesis of imines from a variety of alcohols and amines with the liberation of hydrogen gas. The mechanism has been investigated experimentally with labelled substrates and theoretically with DFT calculations. The results indicate a metal-ligand bifunctional pathway in which both imine groups in the salen ligand are first reduced to form a manganese(iii) amido complex as the catalytically active species. Dehydrogenation of the alcohol then takes place by a stepwise outer-sphere hydrogen transfer generating a manganese(iii) salan hydride from which hydrogen gas is released.

In Situ Generated Cobalt Catalyst for the Dehydrogenative Coupling of Alcohols and Amines into Imines

An in situ formed cobalt catalyst is developed from cobalt(II)bromide, bis[2-(diisopropylphosphino)-4-methylphenyl]amine and zinc metal. The catalyst mediates the acceptorless dehydrogenative coupling of alcohols and amines into imines with the release of hydrogen gas and the transformation is applied to the synthesis of a variety of imines from different alcohols and amines. The mechanism is investigated with labelled substrates and based on the results a cobalt(I) PNP complex is believed to be the catalytically active species which abstracts hydrogen gas from the alcohol through a metal ligand bifunctional pathway.

Phosphine-Free Well-Defined Mn(I) Complex-Catalyzed Synthesis of Amine, Imine, and 2,3-Dihydro-1 H-perimidine via Hydrogen Autotransfer or Acceptorless Dehydrogenative Coupling of Amine and Alcohol

The application of nontoxic, earth-abundant transition metals in place of costly noble metals is a paramount goal in catalysis and is especially interesting if the air- and moisture-stable ligand scaffold is used. Herein, we report the synthesis of amines/imines directly from alcohol and amines via hydrogen autotransfer or acceptorless dehydrogenation catalyzed by well-defined phosphine-free Mn complexes. Both imines and amines can be obtained from the same set of alcohols and amines using the same catalyst, only by tuning the reaction conditions. The amount and nature of the base are found to be a highly important aspect for the observed selectivity. Both the primary and secondary amines have been employed as substrates for the N-alkylation reaction. As a highlight, we showed the chemoselective synthesis of resveratrol derivatives. Furthermore, the Mn-catalyzed dehydrogenative synthesis of structurally important 2,3-dihydro-1H-perimidines has also been demonstrated. Density functional theory calculations were also carried out to model the reaction path and to calculate the reaction profile.

Molybdenum-Catalyzed Dehydrogenative Synthesis of Imines from Alcohols and Amines

A molybdenum N-heterocyclic carbene catalyst has been developed for the synthesis of imines from primary alcohols and amines with the liberation of dihydrogen. The catalyst is generated in situ from molybdenum hexacarbonyl, 1,3-dicyclohexylimidazolium chloride and potassium tert-butoxide and is further stabilized by the phosphine ligand dppe. Imines are formed in moderate to good isolated yields and a variety of alcohols and amines can be employed in the reaction including anilines. The transformation constitutes the first example of a homogeneous molybdenum-catalyzed acceptorless dehydrogenative coupling with alcohols and is believed to proceed by formation of a cis-coordinated molybdenum bis-N-heterocyclic carbene complex, which performs an oxidative addition to the alcohol, β-hydride elimination and reductive elimination of dihydrogen.