76030-55-2Relevant academic research and scientific papers
A Metal-Free Direct Arene C?H Amination
Wang, Tao,Hoffmann, Marvin,Dreuw, Andreas,Hasagi?, Edina,Hu, Chao,Stein, Philipp M.,Witzel, Sina,Shi, Hongwei,Yang, Yangyang,Rudolph, Matthias,Stuck, Fabian,Rominger, Frank,Kerscher, Marion,Comba, Peter,Hashmi, A. Stephen K.
supporting information, p. 2783 - 2795 (2021/04/05)
The synthesis of aryl amines via the formation of a C?N bond is an essential tool for the preparation of functional materials, active pharmaceutical ingredients and bioactive products. Usually, this chemical connection is only possible by transition metal-catalyzed reactions, photochemistry or electrochemistry. Here, we report a metal-free arene C?H amination using hydroxylamine derivatives under benign conditions. A charge transfer interaction between the aminating reagents TsONHR and the arene substrates enables the chemoselective amination of the arene, even in the presence of various functional groups. Oxygen was crucial for an effective conversion and its accelerating role for the electron transfer step was proven experimentally. In addition, this was rationalized by a theoretical study which indicated the involvement of a dioxygen-bridged complex with a “Sandwich-like” arrangement of the aromatic starting materials and the aminating agents at the dioxygen molecule. (Figure presented.).
DIRECT C-H AMINATION AND AZA-ANNULATION
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Paragraph 0132; 0160; 0161; 0162; 0163, (2019/06/07)
In some aspects, the present disclosure provides methods of aminating an aromatic compound comprising reacting an aminating agent with an aromatic compound in the presence of a rhodium catalyst. In some embodiments, the methods may comprise aminating an aromatic compound which contains multiple different functional groups. The methods described herein may also be used to create bicyclic system comprising reacting an intramolecular aminating agent with an aromatic ring to obtain a second ring containing a nitrogen atom. In another aspect, the methods described herein may also be used to create a cyclic aliphatic cyclic/poly cyclic amine system comprising a reacting an intramolecular aminating agent by insertion into a C(sp3)-H bond.
Selective synthesis of mono- and di-methylated amines using methanol and sodium azide as C1 and N1 sources
Chakrabarti, Kaushik,Mishra, Anju,Panja, Dibyajyoti,Paul, Bhaskar,Kundu, Sabuj
supporting information, p. 3339 - 3345 (2018/07/29)
A Ru(ii) complex mediated synthesis of various N,N-dimethyl and N-monomethyl amines from organic azides using methanol as a methylating agent is reported. This methodology was successfully applied for a one-pot reaction of bromide derivatives and sodium azide in methanol. Notably, by controlling the reaction time several N-monomethylated and N,N-dimethylated amines were synthesized selectively. The practical applicability of this tandem process was revealed by preparative scale reactions with different organic azides and synthesis of an anti-vertigo drug betahistine. Several kinetic experiments and DFT studies were carried out to understand the mechanism of this transformation.
Dirhodium-catalyzed C-H arene amination using hydroxylamines
Paudyal, Mahesh P.,Adebesin, Adeniyi Michael,Burt, Scott R.,Ess, Daniel H.,Ma, Zhiwei,Kürti, László,Falck, John R.
, p. 1144 - 1147 (2016/11/09)
Primary and N-alkyl arylamine motifs are key functional groups in pharmaceuticals, agrochemicals, and functional materials, as well as in bioactive natural products. However, there is a dearth of generally applicablemethods for the direct replacement of aryl hydrogens with NH2/NH(alkyl) moieties. Here, we present a mild dirhodium-catalyzed C-H amination for conversion of structurally diverse monocyclic and fused aromatics to the corresponding primary and N-alkyl arylamines using NH2/NH(alkyl)-O-(sulfonyl)hydroxylamines as aminating agents; the relatively weak RSO2O-N bond functions as an internal oxidant. The methodology is operationally simple, scalable, and fast at or below ambient temperature, furnishing arylamines in moderate-to-good yields and with good regioselectivity. It can be readily extended to the synthesis of fused N-heterocycles.
Synthesis of casimiroin and optimization of its quinone reductase 2 and aromatase inhibitory activities
Maiti, Arup,Reddy, P. V. Narasimha,Sturdy, Megan,Marler, Laura,Pegan, Scott D.,Mesecar, Andrew D.,Pezzuto, John M.,Cushman, Mark
experimental part, p. 1873 - 1884 (2009/12/31)
An efficient method has been developed to synthesize casimiroin (1), a component of the edible fruit of Casimiroa edulis, on a multigram scale in good overall yield. The route was versatile enough to provide an array of compound 1 analogues that were evaluated as QR2 and aromatase inhibitors. In addition, X-ray crystallography studies of QR2 in complex with compound 1 and one of its more potent analogues has provided insight into the mechanism of action of this new series of QR2 inhibitors. The initial biological investigations suggest that compound 1 and its analogues merit further investigation as potential chemopreventive or chemotherapeutic agents.
Amination of arenes with N,N-dimethyl-2-imidazolidinone O-methoxyacetyloxime
Baldovini, Nicolas,Kitamura, Mitsuru,Narasaka, Koichi
, p. 548 - 549 (2007/10/03)
Treatment of nucleophilic arenes with N,N-dimethyl-2imidazolidinone O-methoxyacetyloxime and SnCl4 produced the corresponding N-arylimines, which were converted to anilines by hydrolysis with CsOH and to N-methylanilines by LiAlH4 reduction.
Synthesis of primary amines and N-methylamines by the electrophilic amination of Grignard reagents with 2-imidazolidinone O-sulfonyloxime
Kitamura, Mitsuru,Chiba, Shunsuke,Narasaka, Koichi
, p. 1063 - 1070 (2007/10/03)
2-Imidazolidinone O-sulfonyloxime reacts with various aryl and alkyl Grignard reagents as an electrophilic amination reagent, giving N-alkylated imines. The resulting imines are transformed to primary amines and N-methyl secondary amines by hydrolysis with CsOH and LiAlH4 reduction, respectively.
Nonclassical 2,4-diamino-8-deazafolate analogues as inhibitors of dihydrofolate reductases from rat liver, Pneumocystis carinii, and Toxoplasma gondii
Gangjee, Aleem,Zhu, Yuanming,Queener, Sherry F.,Francom, Paula,Broom, Arthur D.
, p. 1836 - 1845 (2007/10/03)
The synthesis and biological activity of 42 6-substituted-2,4- diaminopyrido[3,2-d]pyrimidines (2,4-diamino-8-deazafolate analogues) are reported. The compounds were synthesized in improved yields compared to previous classical analogues using modifications of procedures reported previously by us. Specifically, the S-phenyl-; mono-, di-, and trimethoxyphenyl-; and mono-, di-, and trichlorophenyl-substituted analogues with H or CH3 at the N10 position and methyl and trifluoromethyl phenyl ketone analogues with H, C0H3, and CH2C≡CH at the N10 position were synthesized. The S10 and N10 α- and β-naphthyl analogues along with the N10 CH3 analogues were also synthesized. These compounds were evaluated as inhibitors of dihydrofolate reductases (DHFR) from Pneumocystis carinii (pc) and Toxoplasma gondii (tg); selectivity ratios were determined against rat liver (rl) DHFR as the mammalian reference enzyme. Against pcDHFR the IC50 values ranged from 0.038 x 10-6 M for 2,4-diamino-6-[(N-methyl-2'- naphthylamino)methyl]pyrido[3,2-d]pyrimidine (28) to 5.5 x 10-6 M for 2,4- diamino-6-[(2',4'-dimethoxyanilino)methyl]pyrido[3,2-d]pyrimidine (15). N10 methylation in all instances increased potency. None of the analogues were selective for pcDHFR. Against tgDHFR the most potent analogue was 2,4- diamino-6-[(N-methylanilino)methyl]pyrido[3,2-d]pyrimidine (5) (IC50 0.0084 x 10-6 M) and the least potent was 2,4-diamino-6-[(2'- naphthylamino)methyl]-pyrido[3,2-d]pyrimidine (37) (IC50 0.16 x 10-6 M). N10 methylation afforded an increase in potency up to 10-fold. In contrast to pcDHFR, several of the 8-deaza analogues were significantly selective for tgDHFR, most notably 2,4-diamino-6-[(2'-chloro-N- methylanilino)methyl]pyrido[3,2-d]pyrimidine (13), 2,4-diamino-6-[(3',4',5'- trimethoxyanilino)methyl]pyrido-[3,2-d]pyrimidine (29), and 2,4-diamino-6- [(2',4',6'-trichloroanilino)methyl]pyrido[3,2-d]pyrimidine (32) which combined high potency at 10-8 M along with selectivities of 8.0, 5.0, and 12.4, respectively. The potency of these three analogues are comparable to the clinically used agent trimetrexate while their selectivities for tgDHFR are 17-43-fold better than trimetrexate.
Quinoline Alkaloids. Part 20. Synthesis of Ptelefolone and O-Methylribaline. Ring Closure of Epoxides of 3-Prenylquinolones
Gaston, John L.,Grundon, Michael F.
, p. 2294 - 2299 (2007/10/02)
2-(1-Hydroxy-1-methylethyl)-6,8-dimethoxy-9-methyl-2,3-dihydrofuroquindiolin-4(9H)-one (5a) and its 8-monomethoxy-analogue O-methylribaline (5d) were prepared from 3-prenylquinolones.Reaction of the N-methyl-4-quinolone (5a) with triphenyl phosphite dichloride gave ptelefolone (9) and the asymmetric synthesis of the alkaloid was explored.Ring closure of epoxides of 3-prenylquinolones in basic and non-basic media is discussed.
