36794-50-0

Upstream product

• 110-89-4 piperidine 
• 34713-70-7 2-Phenylpropanal 
• 66217-89-8 1-((E)-2-Phenyl-propenyl)-piperidine 
• 100-42-5 styrene 
• 201230-82-2 carbon monoxide 
• 98-83-9 isopropenylbenzene 

Relevant academic research and scientific papers

Ambient Moisture Accelerates Hydroamination Reactions of Vinylarenes with Alkali-Metal Amides under Air

A straightforward alkali-metal-mediated hydroamination of styrenes using biorenewable 2-methyltetrahydrofuran as a solvent is reported. Refuting the conventional wisdom of the incompatibility of organolithium reagents with air and moisture, shown here is that the presence of moisture is key in favoring formation of the target phenethylamines over competing olefin polymerization products. The method is also compatible with sodium amides, with the latter showing excellent promise as highly efficient catalysts under inert atmosphere conditions.

Highly efficient and eco-friendly synthesis of tertiary amines by reductive alkylation of aldehydes with secondary amines over a Pt nanowires catalyst

Plentiful tertiary amine derivates are synthesized by direct formation of tertiary amines by the interaction of aldehydes with secondary amines over Pt nanowires under mild conditions. This method offers a green and rapid approach to transform secondary amines into various tertiary amines.

Homogeneous and semi-heterogeneous magnetically retrievable bis-n-heterocyclic carbene rhodium(I) based catalysts for selective hydroaminomethylation reactions

The preparation of various bis-N-heterocyclic carbene (bis-NHC) complexes of rhodium and their application in the hydroaminomethylation of vinyl arenes was investigated. Various reaction parameters such as solvent, temperature, and pressure were tested, and the optimized protocol was applied to a wide variety of vinyl arenes and amines to afford the corresponding amines in good yields with high selectivity towards the branched product. The bis-NHC-based catalyst demonstrated superior reactivity and selectivity compared to catalysts containing bidentate phosphine or monodentate NHC ligands. A triethoxysilyl-functionalized bis-NHC ligand was immobilized on magnetic nanoparticles and then utilized to bind a rhodium catalyst. The resulting catalytic system was successfully employed in hydroaminomethylation reactions. The catalyst exhibited excellent reactivity, high selectivity, and was simply recovered from the reaction medium by applying an external magnetic field. Various bis-N-heterocyclic carbene (bis-NHC) ligands are prepared and complexed with rhodium(I). Some of these complexes show excellent reactivity and high selectivity in homogeneous hydroaminomethylation reactions. A bis-NHC ligand derivative is supported on magnetite nanoparticles and after complexation with RhI is was applied successfully in semi-heterogeneous hydroaminomethylations.

Hydroaminomethylation of styrene catalyzed by rhodium complexes containing chiral diphosphine ligands and mechanistic studies: Why is there a lack of asymmetric induction?

Various chiral diphosphine ligands (P-P) have been introduced in the coordination sphere of neutral or cationic rhodium complexes, and the generated species catalyze efficiently the hydroaminomethylation reaction of styrene with piperidine. The diphospholane ligand family is particularly adapted to this tandem reaction leading to the branched amine with good chemo- and regioselectivity. We analyzed in detail the main reasons why the reaction proceeds with no enantioselectivity. Catalytic and HP-NMR experiments reveal the presence of the [Rh(H)(CO)2(P-P)] species as the resting state. DFT calculations allow us to elucidate the mechanism of the hydrogenation of the branched (Z) or (E)-enamine. From the [Rh(H)(CO)(P-P)] active species, the coordination of the two enamine isomers, the hydride transfer, the H2 activation, and then the final reductive elimination follow similar energetic pathways, explaining the lack of enantioselectivity for the present substrates. Analysis of the energy-demanding steps highlights the formation of the active species as crucial for this rate-limiting hydrogenation reaction.

Phosphine- and hydrogen-free: Highly regioselective ruthenium-catalyzed hydroaminomethylation of olefins

A highly regioselective ruthenium-catalyzed hydroaminomethylation of olefins is reported. Using easily available trirutheniumdodecacarbonyl an efficient sequence consisting of a water-gas shift reaction, hydroformylation of olefins, with subsequent imine or enamine formation and final reduction is realized. This novel procedure is highly practical (ligand-free, one pot) and economic (low catalyst loading and inexpensive metal). Bulk industrial as well as functionalized olefins react with various amines to give the corresponding tertiary amines generally in high yields (up to 92), excellent regioselectivities (n/iso>99:1), and full chemoselectivity in favor of terminal olefins.

Efficient and regioselective ruthenium-catalyzed hydro-aminomethylation of olefins

An efficient and regioselective ruthenium-catalyzed hydroaminomethlyation of olefins is reported. Key to success is the use of specific 2-phosphino-substituted imidazole ligands and triruthenium dodecacarbonyl as catalyst. Both industrially important alip

Rhodium-catalyzed highly regioselective hydroaminomethylation of styrenes with tetraphosphorus ligands

The highly linear-selective hydroaminomethylation of styrenes is very challenging. Herein, an efficient, highly chemoselective, and linear-selective hydroaminomethylation (l/b up to >99:1) of styrenes using Rh(nbd) 2SbF6 with a pyrrole-based 3,3′,5,5′- substituted tetraphosphorus ligand is documented. This is in sharp contrast to other available processes leading to branched amines and provides a novel atom economic approach to 3-arylpropylamines.

Selective hydroaminomethylation of olefins using simple and efficient Rh-phosphinite complex catalyst

Hydroaminomethylation of various olefins with primary and secondary amines was carried out using a simple and efficient rhodium-phosphinite complex catalyst. The influence of various reaction parameters including the effects of temperature, pressure, catalyst loading, time and solvents has been investigated. The present protocol is general with wider substrate applicability for the synthesis of an important class of aliphatic amines and arylethylamines. High activity and selectivity for amines was achieved with a very good substrate/catalyst molar ratio (turnover number 2500) under mild reaction conditions. Copyright

Cascade synthesis of fenpiprane and related pharmaceuticals via rhodium-catalyzed hydroaminomethylation

A novel rhodium catalytic system with Naphos as ligand was developed for an efficient hydroaminomethylation of 1,1-diphenylethene under relatively mild conditions. This will allow for an atom-economic and environmentally benign synthesis of fenpiprane and related pharmaceuticals.

Heavier alkaline earth catalysts for the intermolecular hydroamination of vinylarenes, dienes, and alkynes

The heavier group 2 complexes [M{N(SiMe3)2} 2]2(1, M = Ca; 2, M = Sr) and [M{CH(SiMe3) 2}2(THF)2] (3, M = Ca; 4, M = Sr) are shown to be effective precatalysts for the intermolecular hydroamination of vinyl arenes and dienes under mild conditions. Initial studies revealed that the amide precatalysts, 1 and 2, while compromised in terms of absolute activity by a tendency toward transaminative behavior, offer greater stability toward polymerization/oligomerization side reactions. In every case the strontium species, 2 and 4, were found to outperform their calcium congeners. Reactions of piperidine with para-substituted styrenes are indicative of rate-determining alkene insertion in the catalytic cycle while the ease of addition of secondary cyclic amines was found to be dependent on ring size and reasoned to be a consequence of varying amine nucleophilicity. Hydroamination of conjugated dienes yielded isomeric products via η3-allyl intermediates and their relative distributions were explained through stereoelectronic considerations. The ability to carry out the hydroamination of internal alkynes was found to be dramatically dependent upon the identity of the alkyne substituents while reactions employing terminal alkynes resulted in the precipitation of insoluble and unreactive group 2 acetylides. The rate law for styrene hydroamination with piperidine catalyzed by [Sr{N(SiMe3) 2}2]2 was deduced to be first order in [amine] and [alkene] and second order in [catalyst], while large kinetic isotope effects and group 2 element-dependent ΔS? values implicated the formation of an amine-assisted rate-determining alkene insertion transition state in which there is a considerable entropic advantage associated with use of the larger strontium center.