56396-63-5

Upstream product

• 1192-28-5 Cyclopentanone oxime 
• 4392-24-9 Cinnamyl bromide 
• 53293-00-8 hex-5-ynoic acid 
• 77758-51-1 methyl hex-5-ynoate 
• 3506-36-3 3-dimethylaminopropiophenone 
• 1001591-87-2 2-cinnamylidenecyclopentanone O-acetyloxime 
• 29526-96-3 1-phenylcyclopropan-1-ol 
• 62170-42-7 cyclopentanone O-ethanoyloxime 
• 7095-09-2 1-phenyl-3-(2-oxocyclopentyl)-1-propanone 
• 16712-16-6 ammonium formate 
• 96-41-3 Cyclopentanol 
• 14593-04-5 3-amino-3-phenyl-1-propanol 
• 1222866-97-8 5,6-diphenyl-3-vinyl-1,2,4-triazine 
• 2298-48-8 3-morpholin-4-yl-1-phenyl-propan-1-one 

Downstream Products

• 97360-41-3 2-phenyl-6,7-dihydro-5H-[1]pyrindine N-oxide 
• 97360-42-4 7-hydroxy-2-phenyl-6,7-dihydro-5H-<1>pyridine 
• 247185-53-1 (S)-7-hydroxy-2-phenyl-6,7-dihydro-5H-<1>pyridine 
• 247185-52-0 (R)-7-hydroxy-2-phenyl-6,7-dihydro-5H-<1>pyridine 
• 912277-30-6 (R)-2-phenyl-6,7-dihydro-5H-[1]pyrindin-7-yl dicyclohexylphosphinite 
• 912277-31-7 (S)-6,7-dihydro-5H-[1]pyrindin-7-yl di-tert-butylphosphinite 

Relevant academic research and scientific papers

Optimized Scalable Synthesis of Chiral Iridium Pyridyl-Phosphinite (Pyridophos) Catalysts

Iridium catalysts with chiral P,N ligands have greatly enhanced the scope of asymmetric olefin hydrogenation because they do not require a coordinating group near the C=C bond like Rh and Ru catalysts. Pyridophos ligands, possessing a conformationally restricted annulated pyridine framework linked to a phosphinite group, proved to be particularly effective, inducing high enantioselectivities in the hydrogenation of a remarkably broad range of substrates. Here we report the development of an efficient scalable synthesis for the two most versatile Ir-pyridophos catalysts, derived from 2-phenyl-8-hydroxy-5,6,7,8-tetrahydroquinoline or the analogue with a five-membered carbocyclic ring, respectively, by modification and optimization of the original synthetic route. The optimized route renders both catalysts readily accessible in multi-gram quantities in analytically pure form in overall yields of 26–37 %, starting from acetophenone and cyclopentanone or cyclohexanone, respectively. A major advantage of the new synthesis is the efficient and practical kinetic resolution of the late-stage pyridyl alcohol intermediates with commercial immobilized Candida antarctica lipase B, giving access to both enantiomers of these catalysts as essentially enantiopure compounds. The catalysts are obtained as crystalline solids, which are air-stable and can be stored for years at ?20 °C without notable decomposition.

4-HO-TEMPO-Catalyzed Redox Annulation of Cyclopropanols with Oxime Acetates toward Pyridine Derivatives

A 4-HO-TEMPO-catalyzed redox strategy for the synthesis of pyridines through the annulation of cyclopropanols and oxime acetates has been developed. This protocol features good functional group tolerance and high chemoselectivity and also promises to be efficient for the late-stage functionalization of skeletons of drugs and natural products. Mechanism studies indicate that the reaction involves the in situ generated α,β-unsaturated ketones and imines as the key intermediates, which are derived from cyclopropanols and oxime acetates via a TEMPO/TEMPOH redox cycle, respectively. The pyridine products are formed as a result of annulation of enones with imines followed by TEMPO-catalyzed oxidative aromatization by excess oxime acetates. This method not only realizes the TEMPO-catalyzed redox reaction but also broadens the frontiers for TEMPO in catalysis.

A Ruthenium Catalyst with Unprecedented Effectiveness for the Coupling Cyclization of - Amino Alcohols and Secondary Alcohols

The ruthenium complex (8-(2-diphenylphosphinoethyl)aminotrihydroquinolinyl)(carbonyl)(hydrido)ruthenium chloride exhibited extremely high efficiency toward the coupling cyclization of -amino alcohols with secondary alcohols. The corresponding products, pyridine or quinoline derivatives, are obtained in good to high isolated yields. On comparison with literature catalysts whose noble-metal loading with respect to -amino alcohols reached 0.5-1.0 mol % for Ru and a record lowest of 0.04 mol % for Ir, the current catalyst achieves the same efficiency with a loading of 0.025 mol % for Ru. The mechanism of acceptorless dehydrogenative condensation (ADC) was proposed on the basis of DFT calculations; in addition, the reactive intermediates were determined by GC-MS, NMR, and single-crystal X-ray diffraction. The catalytic process is potentially suitable for industrial applications.

8-azasteroid fragments: Synthesis and stereochemistry Of 2- arylperhydrocyclopenta [B] pyridines

We have synthesized and characterized eight 2-aryl perhydrocyclopenta[b]pyridines, which form structural motifs on 8-azasteroids. Reduction of corresponding N-hydroxy derivatives with H2-Pd/C (10%) furnished 2-aryl perhydrocyclopenta[b]pyridine

Sequential Michael Addition and Enamine-Promoted Inverse Electron Demanding Diels-Alder Reaction upon 3-Vinyl-1,2,4-triazine Platforms

An original one-pot Michael addition-ihDA/rDA sequence was achieved from 3-vinyl-1,2,4-triazine platforms used as unprecedented Michael acceptors. This sequence provides a novel access to functionalized [2,3]-fused pyridine derivatives via a unique enamin

Quinoline synthesis: Scope and regiochemistry of photocyclisation of substituted benzylidenecyclopentanone O-alkyl and O-acetyloximes

Irradiation of substituted 2-benzylidenecyclopentanone O-alkyl and O-acetyloximes in methanol provides a convenient synthesis of alkyl, alkoxy, hydroxy, acetoxy, amino, dimethylamino and benzo substituted annulated quinolines. para-Substituents yield 6-substituted-2,3-dihydro-1H-cyclopenta[b] quinolines with 8-substituted products being obtained from ortho-substituted starting materials. Reactions of meta-substituted precursors are highly regioselective, with alkyl substituents leading to 5-substituted 2,3-dihydro-1H-cyclopenta[b]quinolines and more strongly electron-donating substituents generally resulting in 7-substituted products. 2-Furylmethylene and 2-thienylmethylene analogues yield annulated furo- and thieno-[2,3e]pyridines respectively. Sequential E- to Z-benzylidene group isomerisation and six π-electron cyclisation steps result in formation of a short-lived dihydroquinoline intermediate which spontaneously aromatises by elimination of an alcohol or acetic acid. For 2-benzylidenecyclopentanone O-allyloxime, singlet excited states are involved in both steps. The Royal Society of Chemistry 2007.

Iridium catalysts with bicyclic pyridine-phosphinite ligands: Asymmetric hydrogenation of olefins and furan derivatives

(Chemical Equation Presented) Superior bicyclics: Iridium catalysts as 1 derived from pyridine-phosphinite ligands considerably extend the scope of asymmetric hydrogenation. In addition to various unfunctionalized and functionalized olefins, furans, and benzofurans, for which no catalysts were known before, are also hydrogenated with high enantioselectivity (see scheme).

Selenium catalyzed conversion of δ-phenyl- γ-alkenyl oximes into 2-phenylpyridines

δ-Phenyl-γ-alkenyl oximes react with an excess of ammonium persulfate and catalytic amounts of diphenyl diselenide in the presence of trifluoromethanesulfonic acid in acetonitrile to afford 2-phenylpyridines and 2-phenylpyridine N-oxides in moderate yields.

Intramolecular Diels-Alder Reactions of 1,2,4-Triazines. Synthesis of 2,3-Cyclopentenopyridines and 5,6,7,8-Tetrahydroquinolines

2,3-Cyclopentenopyridines and 5,6,7,8-tetrahydroquinolines are prepared by intramolecular Diels-Alder reactions of appropriately substituted 1,2,4-triazines.Two general routes to the requisite triazine precursors are described.