31776-82-6

Upstream product

• 584-02-1 2-pentanol 
• 100-46-9 benzylamine 
• 77390-49-9 (Z)-N-(1-Methylpropylidene)-1-phenyl-methanamine 
• 74-88-4 methyl iodide 
• 31776-80-4 3-methyl-1-phenyl-2-azapent-2-ene 
• 96-22-0 pentan-3-one 

Downstream Products

• 88875-58-5 1-benzyl-2-ethylidene-4-hydroxy-5-imino-3-methyl-4-(4-nitrophenyl)-pyrrolidine 
• 1140972-71-9 3-(2-methoxynaphthalen-1-yl)propynoic acid benzyl(1-ethylprop-1-enyl)amide 
• 1100246-25-0 benzyl-(1-ethyl-1-trifluoromethylpropyl)amine 
• 93698-74-9 1-Benzyl-2-ethyl-3,5-dimethyl-1H-pyrrole 
• 61977-85-3 N-benzyl-1-ethylpropylamine 
• 98611-95-1 2-methyl-3-pentanone N-benzylimine 

Relevant academic research and scientific papers

Palladium-Catalyzed Enantioselective Heteroarenyne Cycloisomerization Reaction

The extensively developed ene-type enantioselective cycloisomerization of classical 1,n-enynes provides an efficient approach to chiral cyclic 1,4-dienes. In contrast, the catalytic asymmetric heteroarenyne (heteroarene–alkyne) cycloisomerization involving the dearomative transformation of endocyclic aromatic C=C bonds remains unknown. Herein, we communicate a PdH-catalyzed enantioselective heteroarenyne cycloisomerization reaction of alkyne-tethered indole substrates (formal 1,5- and 1,6-enynes). Based on this strategy, a variety of structurally diverse chiral spiro and fused indoline derivatives bearing quaternary stereocenters and exocyclic C=C bonds are afforded in moderate to excellent yields and excellent enantioselectivities (up to 98 % ee). The classical ene-type enantioselective 1,5-enyne cycloisomerization of N-vinylpropiolamides is also developed to afford chiral 2-pyrrolones in good to excellent ee values.

Modular Photocatalytic Synthesis of α-Trialkyl-α-Tertiary Amines

Molecules displaying an α-trialkyl-α-tertiary amine motif provide access to an important and versatile area of biologically relevant chemical space but are challenging to access through existing synthetic methods. Here, we report an operationally straightforward, multicomponent protocol for the synthesis of a range of functionally and structurally diverse α-trialkyl-α-tertiary amines, which makes use of three readily available components: dialkyl ketones, benzylamines, and alkenes. The strategy relies on the of use visible-light-mediated photocatalysis with readily available Ir(III) complexes to bring about single-electron reduction of an all-alkyl ketimine species to an α-amino radical intermediate; the α-amino radical undergoes Giese-type addition with a variety of alkenes to forge the α-trialkyl-α-tertiary amine center. The mechanism of this process is believed to proceed through an overall redox neutral pathway that involves photocatalytic redox-relay of the imine, generated from the starting amine-ketone condensation, through to an imine-derived product. This is possible because the presence of a benzylic amine component in the intermediate scaffold drives a 1,5-hydrogen atom transfer step after the Giese addition to form a stable benzylic α-amino radical, which is able to close the photocatalytic cycle. These studies detail the evolution of the reaction platform, an extensive investigation of the substrate scope, and preliminary investigation of some of the mechanistic features of this distinct photocatalytic process. We believe this transformation will provide convenient access to previously unexplored α-trialkyl-α-tertiary amine scaffolds that should be of considerable interest to practitioners of synthetic and medicinal chemistry in academic and industrial institutions.

Asymmetric Synthesis of Six-Membered Cyclic Sulfamides via Palladium-Catalyzed Alkene Carboamination Reactions

The asymmetric synthesis of six-membered cyclic sulfamides via palladium-catalyzed alkene carboamination reactions of N -homoallylsulfamides with aryl halides is described. High levels of enantioselectivity were obtained with a catalyst composed of Pd 2 dba 3 and (S)-Siphos-PE.

Catalytic acceptorless dehydrogenations: Ru-Macho catalyzed construction of amides and imines

A commercially available ruthenium(II) PNP type pincer catalyst (Ru-Macho) promotes formation of amides and imines from alcohols and amines via an acceptorless dehydrogenation pathway. The formation of secondary amides, tertiary amides, and secondary ketimines occurs in yields ranging from 35% to 95%.

An easy synthesis of α-trifluoromethyl-amines from aldehydes or ketones using the Ruppert-Prakash reagent

A small library of structurally diverse primary amines bearing a geminal CF3 group was synthesized on a preparative scale. The synthesis starts with an aldehyde or ketone that reacts with benzylamine yielding the corresponding imine. The latter is then trifluoromethylated with Me 3SiCF3 under acidic conditions to give a benzylalkylamine. In the last step the Pd-mediated hydrogenation of the benzylalkylamines furnishes the title compounds. All synthetic steps are high-yielding; neither the isolation of the intermediates nor the chromatographic purification of the products is necessary.

Highly enantioselective construction of axial chirality by palladium-catalyzed cycloisomerization of N- alkenyl arylethynylamides

A cationic palladium(ll)/(S)-xyl-Segphos complex catalyzes enantioselective cycloisomerizations of N-alkenyl arylethynylamldes leading to axlally chlral 4-aryl-2-pyridones In high yields with high ee values. The present catalysis represents the first enantioselective construction of axial chlrallty by the transition-metal-catalyzed cyclolsomerlzatlon.

Nucleophilic trifluoromethylation of imines under acidic conditions

A general method for the trifluoromethylation of imines by using Me 3SiCF3 under acidic conditions is described. The reaction is promoted by hydrofluoric acid generated in situ from KHF2 and either TFA or TfOH. A new chemoselectivity pattern was achieved, as the C=N bond was found to be more reactivate than the carbonyl group. The trifluoromethylation reaction is believed to proceed by concerted transfer of the CF3 group from the silicon atom to the iminium electrophile. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.

Metal-catalysed radical cyclisations leading to N-heterocycles: New approaches to gabapentin and pulchellalactam

The copper(I) or ruthenium(II)-mediated radical cyclisation of halo-amides has been utilised to afford functionalised pyrrolidinones via 5-endo-trig or 5-exo-trig radical cyclisation pathways. This methodology has been applied to novel and concise syntheses of the anti-epileptic drug gabapentin and the biologically active natural product pulchellalactam.

Formation and Isomerization of 2-Azaallyllithium Reagents in Deprotonations of N-Benzyl Ketimines Containing α-Protons

Deprotonation of the N-benzylimine of 3-pentanone by lithium diisopropylamide (LDA) in tetrahydrofuran occurs at the benzylic position to give a 2-azaallyllithium reagent in high yield.On standing, the 2-azaallyllithium reagent isomerizes to a 1-azaallyllithium reagent.The N-benzylimine of 2-butanone can be similarly deprotonated by LDA at the benzylic position in competition with deprotonation at the α-positions to give a 2-azaallyllithium reagent in up to 22percent yield.The N-benzylimine of acetone is not appreciably deprotonated at the benzylic position by LDA.Kinetic studies of the isomerization of 2-azaallyl- to 1-azaallyllithium reagent from the 3-pentanone imine suggest that this reaction proceeds by a protonation-deprotonation sequence.

Factors Controlling Regioselectivity in Deprotonations of Unsymmetrical Ketimines

The regioselectivity of deprotonation of equilibrium E-Z mixtures of the benzyl, n-butyl, cyclohexyl, phenyl, and tert-butyl imines of 2-butanone by lithium diisopropylamide (LDA) in tetrahydrofuran has been shown to be a function of both the nitrogen substituent and the temperature of the deprotonation reaction.High regioselectivity at either the methyl or methylene substituent could be obtained for all imines except the benzyl and n-butyl imines.Pure (Z)-2-butanone imines (R = n-C4H9, c-C6H11, t-C4H9), prepared by LDA deprotonation of acetone imines followed by methylation, were deprotonated by LDA at the methyl position at -78 deg C and at 0 deg C.Studies of the rates of deprotonation of the E and Z isomers of n-butyl, cyclohexyl, and tert-butyl imines of 2-butanone and of the rates and mechanisms of isomerizations of these isomeric ketimines were performed.Temperature dependent deprotonation regioselectivity was also observed in lithium diethylamide deprotonations of the benzyl, cyclohexyl, phenyl, and tert-butyl imines of 2-butanone.A general scheme accounting for these results and other accounts of variable regioselectivity in ketimine deprotonation is presented.