3649-46-5

Upstream product

• 84941-60-6 2-Phenyl-5,6,7,8-tetrahydro-imidazo<1,2-a>pyridin-1-oxid 
• 42564-23-8 2-Phenyl-6,7,8,8a-tetrahydro-3H,5H-imidazo<1,2-a>pyridin-1-oxid 
• 670-95-1 4-Phenylimidazole 
• 16011-96-4 2-iminopiperidine hydrochloride 
• 70-11-1 α-bromoacetophenone 
• 41208-54-2 2-phenyl-2,3,5,6,7,8-hexahydro-imidazo[1,2-a]pyridine 
• 100-42-5 styrene 
• 4636-16-2 iodoacetophenone 
• 4105-21-9 2-phenylimidazo[1,2-a]pyridine 
• 504-29-0 2-aminopyridine 
• 100-52-7 benzaldehyde 
• 98-86-2 acetophenone 

Relevant academic research and scientific papers

Hydrogenation reaction method

The invention relates to a hydrogenation reaction method, and belongs to the technical field of organic synthesis. The hydrogenation reaction method provided by the invention comprises the following steps: carrying out a hydrogen transfer reaction on a hydrogen acceptor compound, pinacol borane and a catalyst in a solvent in the presence of proton hydrogen, so that the hydrogen acceptor compound is subjected to a hydrogenation reaction; the catalyst is one or more than two of a palladium catalyst, an iridium catalyst and a rhodium catalyst; the hydrogen acceptor compound comprises one or morethan two functional groups of carbon-carbon double bonds, carbon-carbon triple bonds, carbon-oxygen double bonds, carbon-nitrogen double bonds, nitrogen-nitrogen double bonds, nitryl, carbon-nitrogentriple bonds and epoxy. The method is mild in reaction condition, easy to operate, high in yield, short in reaction time, wide in substrate application range, suitable for carbon-carbon double bonds,carbon-carbon triple bonds, carbon-oxygen double bonds, carbon-nitrogen double bonds, nitrogen-nitrogen double bonds, nitryl, carbon-nitrogen triple bonds and epoxy functional groups, good in selectivity and high in reaction specificity.

Generalized Chemoselective Transfer Hydrogenation/Hydrodeuteration

A generalized, simple and efficient transfer hydrogenation of unsaturated bonds has been developed using HBPin and various proton reagents as hydrogen sources. The substrates, including alkenes, alkynes, aromatic heterocycles, aldehydes, ketones, imines, azo, nitro, epoxy and nitrile compounds, are all applied to this catalytic system. Various groups, which cannot survive under the Pd/C/H2 combination, are tolerated. The activity of the reactants was studied and the trends are as follows: styrene'diphenylmethanimine'benzaldehyde'azobenzene'nitrobenzene'quinoline'acetophenone'benzonitrile. Substrates bearing two or more different unsaturated bonds were also investigated and transfer hydrogenation occurred with excellent chemoselectivity. Nano-palladium catalyst in situ generated from Pd(OAc)2 and HBPin extremely improved the TH efficiency. Furthermore, chemoselective anti-Markovnikov hydrodeuteration of terminal aromatic olefins was achieved using D2O and HBPin via in situ HD generation and discrimination. (Figure presented.).

Visible Light as a Sole Requirement for Intramolecular C(sp3)-H Imination

A novel, simple, and practical visible-light-mediated intramolecular α-C(sp3)-H imination of tertiary aliphatic amines containing β-O-aryl oximes leading to N-heterocycles has been developed. The reaction was performed well at rt with tolerance of some functional groups. Importantly, the selective C-H functionalization did not require added catalyst, oxidant, additive, acid, and base; visible light was the sole requirement.

Diboron-assisted palladium-catalyzed transfer hydrogenation of N-heteroaromatics with water as hydrogen donor and solvent

A Pd-catalyzed transfer hydrogenation of various N-heteroaromatic compounds with B2pin2 as a mediator and environmentally benign water as both solvent and hydrogen donor has been disclosed. This reaction proceeded under ambient temperature with a broad range of N-heteroaromatic compounds among which imidazo[1,2-a]pyridine derivatives were for the first time selectively reduced to 5,6,7,8-tetrahydroimidazo[1,2-a]pyridines, which are the core structural motifs of an inhibitor of human O-GlcNAcase. Mechanistic studies suggested that the new protons in products are from water and Pd-H might be the key intermediate with B2pin2 as the H2O activator.

Reduction method of nitrogen-containing heterocyclic compound

The invention discloses a reduction method of a nitrogen-containing heterocyclic compound. The reduction method comprises the following steps: firstly, adding bis(pinacolato)diboron, palladium acetate and cesium carbonate into a pressure-resisting sealing reaction vessel; filling with nitrogen, adding water and quinoline compounds, performing stirring reaction at room temperature, and tracking by using TLC and GC in a reaction process so as to decide specific reaction time; secondly, after the reaction is ended, taking out a reaction product in the first step from the pressure-resisting sealing reaction vessel, cooling to room temperature, then adding ethyl acetate for fully mixing, and subsequently performing filtering and washing of ethyl acetate to obtain an organic phase; thirdly, performing spin drying on a solvent in the organic phase obtained in the second step, purifying by using a silica gel column, and then leaching with an eluant to obtain a product. The eluant is a mixed solution of petroleum ether and the ethyl acetate. The reduction method disclosed by the invention accords with the idea of green chemistry, and is better in economy and simple in operation.

Direct preparation of thiazoles, imidazoles, imidazopyridines and thiazolidines from alkenes

A range of heterocycles, namely thiazoles, imidazoles, imidazopyridines, thiazolidines and dimethoxyindoles, have been synthesised directly from alkenes via a two-step ketoidoination/cyclisation protocol. The alkene starting materials are themselves readily accessible using many different and well-established approaches, and allow access to a variety of heterocycles with excellent yields and regioselectivity.

Regioselectivity in the dehydrogenation of substituted ethylenediamines as nicotine models

The direction of dehydrogenation with Hg(II)-EDTA of 2-substituted pyrrolidines and piperidines is examined at the model substances 1-4 featuring a N-(2-amino-2-phenylethyl) substituent, which is able to capture an iminium intermediate. Compounds 1-4 repr

Hydroxylamine function as neighboring group with dehydrogenations

The β-amino-hydroxylamines 5a-d are prepared of the α-amino-oximes 1a-d with borane-dimethylsulfide. With mercury-EDTA, 5a-d react to (E/Z)-oxime-lactams 3a-d and benzaldoxime 7. Additionally 5b,c give the bicyclic amidine-N-oxides 8b,c, which slowly hydrolyze to the hydroxylamine-lactams 9b,c. These are easily oxidized to (E/Z)-3b,c. Postulated as intermediates in the mercury-assisted reduction of 5, the cyclic hydroxylamines 10a-d are available from the nitrones 4a-d with LiAlH 4. From 10a-d with mercury-EDTA the same products are obtained as from 5a-d but without 7. Only the pyrrolidine 10a forms besides (E/Z)-3a the nitrone 4a. Thin-layer chromatography shows that the pure isomers of 3a-d in solution isomerize, contrary to the amine-oximes 1a-d. The configuration of the oxime-lactams depends on the manner of preparation. With mercury-EDTA, 1b,c yield 3b,c with retention of the configuration, while the oximation of phenacyl-lactams 13b,c give rise to (E/Z)-mixtures of 3b,c. The condensed imidazoles 12 result from the nitrones 4a-d and the dihydrooxadiazines 2a,d on treatment with hydrogen chloride.

Bu3SnH mediated oxidative radical cyclisation onto imidazoles and pyrroles

A new protocol using radical cyclisation has been developed for the synthesis of [1,2-c]-fused imidazoles and [1,2-a]-fused pyrroles. The intermediate nucleophilic N-alkyl radicals, generated using Bu3SnH from N- (ω-bromoalkyl) or N-[ω-(phenylselanyl)alkyl] imidazoles and pyrroles, undergo regio-selective radical cyclisalion onto the azole rings followed by oxidative re-aromatisation.