- Single-atom Fe-N4site for the hydrogenation of nitrobenzene: theoretical and experimental studies
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The hydrogenation of nitrobenzene to aniline is an important process in the industry of fine chemicals, but developing inexpensive catalysts with expected activity and selectivity still remains a challenge. By using density functional theory calculations, we demonstrated that the isolated Fe atom not only can weaken the adsorption of reactants and reaction intermediates as compared to Fe nanoparticles, but also remarkably decrease the reaction barrier for the hydrogenation of nitrobenzene to aniline. Thus, the Fe single-atom (Fe SA) catalyst is considered as an ideal catalyst for this reaction. This theoretical prediction has been subsequently confirmed by experimental results obtained for the Fe SAs loaded on N-doped hollow carbon spheres (Fe SAs/NHCSs) which achieved a conversion of 99% with a selectivity of 99% for the hydrogenation of nitrobenzene. The results significantly outperformed the Fe nanoparticles for this reaction. This work provides theoretical insight for the rational design of new catalytic systems with excellent catalytic properties.
- Dong, Panpan,He, Rong,Liu, Yan,Lu, Ning,Mao, Junjie,Wu, Konglin,Zhang, Wenzhuang,Zheng, Yamin
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- NMR studies of chiral discrimination relevant to the liquid chromatographic enantioseparation by a cellulose phenylcarbamate derivative
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Chromatographic enantioseparation of 1,1'-bi-2-naphthol (2) and its mono- and di-O-methylated derivatives (3a, 3b), 2,2'-dihydroxy-6,6'-dimethylbiphenyl (4), and 10,10'-dihydroxy-9,9'-biphenanthryl (5) has been performed on cellulose tris(5-fluoro-2-methylphenylcarbamate) (1) as a chiral stationary phase for high-performance liquid chromatography (HPLC). The complete base-line separation of 2 and 4 was achieved with the elution order of enantiomers such that the (R)-isomers eluted first followed by the (S)-isomers. The resolution of 5 and the O-methylated 3 was difficult on 1. The cellulose derivative 1 dissolved in chloroform also exhibited a chiral discrimination for 2 and 4 in 1H and 13C NMR spectroscopies as well as in HPLC. The hydroxy and some aromatic protons and carbon resonances of 2 and 4 were clearly separated into a pair of peaks due to enantiomers in the presence of 1. The binding geometry and dynamics between 1 and the enantiomers of 2 were investigated on the basis of spin-lattice relaxation time, 1H NMR titrations, and intermolecular NOEs in the presence of 1. These NMR data are fully consistent with the chromatographic elution order. These results, combined with molecular modeling, reveal the chiral discrimination rationale.
- Yashima, Eiji,Yamamoto, Chiyo,Okamoto, Yoshio
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- Highly chemoselective reduction of azides to amines by Fe(0) nanoparticles in water at room temperature
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A highly chemoselective reduction of aryl, heteroaryl, acyl and sulfonyl azides to the corresponding amines has been achieved by Fe(0) nanoparticles in water at room temperature in the absence of external hydride source. Several readily reducible functionalities including alkene, alkyne, S-S linkage, OTBDMS remain unaffected during reduction.
- Panja, Subir,kundu, Debasish,Ahammed, Sabir,Ranu, Brindaban C.
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supporting information
p. 3457 - 3460
(2017/08/10)
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- Indazole Compounds as IRAK4 Inhibitors
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The present invention provides indazole compounds of formula (I), which are therapeutically useful as kinase inhibitors, particularly IRAK4 inhibitors, wherein Z1, Z2, R1, R2, R3, ‘m’ and ‘n’ have the meanings given in the specification, and pharmaceutically acceptable salts or stereoisomers thereof that are useful in the treatment and prevention of diseases or disorders, in particular their use in diseases or disorders mediated by kinase enzyme, particularly IRAK4 enzyme. The present invention also provides pharmaceutical compositions comprising at least one of the compounds of the compound of formula (I) together with a pharmaceutically acceptable carrier, diluent or excipient.
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Paragraph 0204
(2016/11/28)
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- INDAZOLE COMPOUNDS AS IRAK4 INHIBITORS
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The present invention provides indazole compound of formula (I), which are therapeutically useful as kinase inhibitor, particularly IRAK4 inhibitors. wherein Z1, Z2, R1, R2, R3, 'm' and 'n' have the meanings given in the specification, and pharmaceutically acceptable salts or stereoisomers thereof that are useful in the treatment and prevention of diseases or disorder, in particular their use in diseases or disorder mediated by kinase enzyme, particularly IRAK4 enzyme. The present invention also provides pharmaceutical composition comprising at least one of the compounds of compound of formula (I) together with a pharmaceutically acceptable carrier, diluent or excipient therefor.
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Page/Page column 37
(2015/07/23)
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- Palladium-catalyzed amination of aryl chlorides and bromides with ammonium salts
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We report the palladium-catalyzed coupling of aryl halides with ammonia and gaseous amines as their ammonium salts. The coupling of aryl chlorides and ortho-substituted aryl bromides with ammonium sulfate forms anilines with higher selectivity for the primary arylamine over the diarylamine than couplings with ammonia in dioxane. The resting state for the reactions of aryl chlorides is different from the resting state for the reactions of aryl bromides, and this change in resting states is proposed to account for a difference in selectivities for reactions of the two haloarenes.
- Green, Rebecca A.,Hartwig, John F.
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supporting information
p. 4388 - 4391
(2015/01/08)
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- An examination of the palladium/Mor-DalPhos catalyst system in the context of selective ammonia monoarylation at room temperature
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An examination of the [{Pd(cinnamyl)Cl}2]/Mor-DalPhos (Mor-DalPhos=di(1-adamantyl)-2-morpholinophenylphosphine) catalyst system in Buchwald-Hartwig aminations employing ammonia was conducted to better understand the catalyst formation process and to guide the development of precatalysts for otherwise challenging room-temperature ammonia monoarylations. The combination of [{Pd(cinnamyl)Cl}2] and Mor-DalPhos afforded [(κ 2-P,N-Mor-DalPhos)Pd(η1-cinnamyl)Cl] (2), which, in the presence of a base and chlorobenzene, generated [(κ2-P,N- Mor-DalPhos)Pd(Ph)Cl] (1 a). Halide abstraction from 1 a afforded [(κ3-P,N,O-Mor-DalPhos)Pd(Ph)]OTf (5), bringing to light a potential stabilizing interaction that is offered by Mor-DalPhos. An examination of [(κ2-P,N-Mor-DalPhos)Pd(aryl)Cl] (1 b-f) and related precatalysts for the coupling of ammonia and chlorobenzene at room temperature established the suitability of 1 a in such challenging applications. The scope of reactivity for the use of 1 a (5 mol %) encompassed a range of (hetero)aryl (pseudo)halides (X=Cl, Br, I, OTs) with diverse substituents (alkyl, aryl, ether, thioether, ketone, amine, fluoro, trifluoromethyl, and nitrile), including chemoselective arylations. Copyright
- Alsabeh, Pamela G.,Lundgren, Rylan J.,McDonald, Robert,Johansson Seechurn, Carin C. C.,Colacot, Thomas J.,Stradiotto, Mark
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supporting information
p. 2131 - 2141
(2013/03/14)
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- NOVEL CATALYSTS
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The present invention provides novel compounds and ligands that are useful in transition metal catalyzed cross-coupling reactions. For example, the compounds and ligands of the present invention are useful in palladium or gold catalyzed cross-coupling reactions.
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Page/Page column 65
(2012/06/01)
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- A P,N-Ligand for palladium-catalyzed ammonia arylation: Coupling of deactivated aryl chlorides, chemoselective arylations, and room temperature reactions
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(Figure Presented) Amazing ammonia: A new air-stable P,N-ligand (Mor-DalPhos) is reported that enables the palladium-catalyzed crosscoupling of ammonia to a variety of aryl chloride and aryl tosylate substrates with high chemoselectivity and, for the first time, at room temperature (see scheme; Ad = adamantyl, Ts=para-toluenesulfonyl).
- Lundgren, Rylan J.,Peters, Brendan D.,Alsabeh, Pamela G.,Stradiotto, Mark
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supporting information; experimental part
p. 4071 - 4074
(2010/07/05)
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- A highly versatile catalyst system for the cross-coupling of aryl chlorides and Amines
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The syntheses of 2-(di-tertbutylphosphino)-N,N-dimethylaniline (L1, 71%) and 2-(di-1-adamantylphosphino)-N,N-dimethylaniline (L2, 74%), and their application in BuchwaldHartwig amination, are reported. In combination with [Pd(allyl)Cl]2 or [Pd(cinnamyl)Cl]2, these structurally simple and air-stable P,N ligands enable the cross-coupling of aryl and heteroaryl chlorides, including those bearing as substituents enolizable ketones, ethers, esters, carboxylic acids, phenols, alcohols, olefins, amides, and halogens, to a diverse range of amine and related substrates that includes primary alkyl- and arylamines, cyclic and acyclic secondary amines, N-H imines, hydrazones, lithium amide, and ammonia. In many cases, the reactions can be performed at low catalyst loadings (0.5-0.02 mol % Pd) with excellent functional group tolerance and chemoselectivity. Examples of cross-coupling reactions involving 1,4-bromochlorobenzene and iodobenzene are also reported. Under similar conditions, inferior catalytic performance was achieved when using Pd(OAc)2, PdCl2, [PdCl2(cod)] (cod = 1,5-cyclooctadiene), [PdCl 2(MeCN)2], or [Pd2(dba)3] (dba = dibenzylideneacetone) in combination with L1 or L2, or by use of [Pd(allyl)Cl]2 or [Pd(cinnamyl)Cl]2 with variants of L1 and L2 bearing less basic or less sterically demanding substituents on phosphorus or lacking an ortto-dimethylamino fragment. Given current limitations associated with established ligand classes with regard to maintaining high activity across the diverse possible range of C-N coupling applications, L1 and L2 represent unusually versatile ligand systems for the cross-coupling of aryl chlorides and amines
- Lundgren, Rylan J.,Sappong-Kumankumah, Antonia,Stradiotto, Mark
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experimental part
p. 1983 - 1991
(2010/07/03)
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- 4-Substituted indazoles as new inhibitors of neuronal nitric oxide synthase
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A series of halo-1-H-indazoles has been synthesized and evaluated for its inhibitory activity on neuronal nitric oxide synthase. Introduction of bromine at the C4 position of the indazole ring system provided a compound almost as potent as the reference compound, that is, 7-nitroindazole (7-NI). The importance of position 4 is further demonstrated by the synthesis and pharmacological evaluation of the 4-nitroindazole which was also a potent inhibitor of NOS activity. These compounds also exhibited in vivo NOS inhibitory activity, as attested by potent antinociceptive effects following systemic administration.
- Boulouard, Michel,Schumann-Bard, Pascale,Butt-Gueulle, Sabrina,Lohou, Elodie,Stiebing, Silvia,Collot, Valerie,Rault, Sylvain
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p. 3177 - 3180
(2008/02/04)
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- SUBSTITUTED QUINAZOLINE DERIVATIVES AND THEIR USE AS INHIBITORS
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The use of a compound of formula (I) 1 or a salt, ester or amide thereof; where X is O, or S, S(O) or S(O)2, or NR6 where R6 is hydrogen or C1-6 alkyl,; R5 is an optionally substituted 5-membered heteroaromatic ring, R1, R2 ,R3, R4 are independently selected from various specified moieties, in the preparation of a medicament for use in the inhibition of aurora 2 kinase. Certain compounds are novel and these, together with pharmaceutical compositions containing them are also described and claimed
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- Synthesis of aromatic amines using allyl azide
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Aromatic amines are conveniently prepared in good yields by reaction of aromatic Grignard and lithium reagents with allyl azide, followed by hydrolysis.
- Kabalka, George W.,Li, Guisheng
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p. 5777 - 5778
(2007/10/03)
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- Intramolecular Selectivity of the Alkylation of Substituted Anilines by Gaseous Cations
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The intramolecular selectivity of the electrophilic reactions of Et(1+), i-Pr(1+), and Me2F(1+) cations with substituted anilines, including m-toluidine, m-anisidine, and m- and p-fluoroaniline, has been investigated in the dilute gas state at pressures ranging from 100 to 720 torr by a radiolytic technique, complemented by chemical ionization mass spectrometry.The results indicate an appreciable kinetic bias for the nitrogen atom, leading to predominant N-methylation by Me2F(1+).The reactivity of the carbenium ions is complicated by the simultaneous occurrence of proton transfer, in particular to the NH2 group, which increases the relative extent of ring alkylation.The positional selectivity is characterized, aside from the usual orienting effects of the substituents, by the enchanced reactivity of the ring positions ortho to an n-type substituent, irrespective of its activating or deactivating properties.The effect is traced to the preliminary formation of an electrostatic adduct between the aniline and the gaseous electrophile.
- Attina, Marina,Cacace, Fulvio,de Petris, Giulia
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p. 1556 - 1561
(2007/10/02)
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- 3 Fluoro-10-piperazino-8-substituted 10,11-dihydrodibenzo-(bf) thiepins and method for the preparation thereof
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Techniques for the preparation of 3-fluoro-10-piperazino-8-substituted 10,11-dihydrodibenzo-(b,f) thiepins and their addition salts with organic and inorganic acids are disclosed. The described compositions evidence psychotropic activity and low toxicity and are characterized as neuroliptics with a high degree of cataleptic, anti-apomorphine and central depressant action.
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- Indenylacetic acid compounds
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4, 5, 6 or 7 Aryl substituted indenyl acetic acids and pharmaceutically acceptable salts, amides and esters thereof. The 4, 5, 6 or 7 aryl substituted indenyl acetic acids have anti-inflammatory, anti-pyretic and analgesic activity. The invention also includes methods for the preparation of these compounds, pharmaceutical compositions and methods of treating inflammation by administering these particular compounds to patients.
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