- A Greener Approach for the Chemoselective Boc Protection of Amines Using Sulfonated Reduced Graphene Oxide as a Catalyst in Metal- And Solvent-Free Conditions
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Sulfonated reduced graphene oxide (SrGO) has displayed great potential as a solid acid catalyst due to its efficiency, cost-effectiveness, and reliability. In this study, SrGO was synthesized by the introduction of sulfonic acid-containing aryl radicals onto chemically reduced graphene oxide using ultrasonication. The SrGO catalyst was characterized by Fourier Transform Infrared (FTIR) spectroscopy, Raman spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). Further, SrGO was effectively utilized as a metal-free and reusable solid acid catalyst for the chemoselective N - t -Boc protection of various aromatic and aliphatic amines under solvent-free conditions. The N - t -Boc protection of amines was easily achieved under ambient conditions affording high yields (84-95percent) in very short reaction times (5 min-2 h). The authenticity of the approach was confirmed by a crystal structure. The catalyst could be easily recovered and was reused up to seven consecutive catalytic cycles without any substantial loss in its activity.
- Awasthi, Satish K.,Mishra, Anupam,Mittal, Rupali
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- ARYL SULFONAMIDES AS SMALL MOLECULE STAT3 INHIBITORS
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The present disclosure provides pharmaceutical compositions comprising aryl sulfonamide Stat3 small molecule inhibitors and certain pharmaceutically acceptable salts thereof, and methods of their use for treating cancer.
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Paragraph 00513; 00516
(2021/01/29)
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- Development of Potent 3-Br-isoxazoline-Based Antimalarial and Antileishmanial Compounds
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Starting from the structure of previously reported 3-Br-isoxazoline-based covalent inhibitors of P. falciparum glyceraldehyde 3-phosphate dehydrogenase, and with the intent to improve their metabolic stability and antimalarial activity, we designed and synthesized a series of simplified analogues that are characterized by the insertion of the oxadiazole ring as a bioisosteric replacement for the metabolically labile ester/amide function. We then further replaced the oxadiazole ring with a series of five-membered heterocycles and finally combined the most promising structural features. All the new derivatives were tested in vitro for antimalarial as well as antileishmanial activity. We identified two very promising new lead compounds, endowed with submicromolar antileishmanial activity and nanomolar antiplasmodial activity, respectively, and a very high selectivity index with respect to mammalian cells.
- Basilico, Nicoletta,Conti, Paola,Coser, Consuelo,Galbiati, Andrea,Parapini, Silvia,Tamborini, Lucia,Taramelli, Donatella,Zana, Aureliano
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supporting information
p. 1726 - 1732
(2021/11/01)
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- Tert-Butyl(3-cyano-4,6-dimethylpyridin-2-yl)carbonate as a green and chemoselective N-tert-butoxycarbonylation reagent
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The use of tert-butyl(3-cyano-4,6-dimethylpyridin-2-yl)carbonate as a chemoselective tert-butoxycarbonylation reagent for aromatic and aliphatic amines has been demonstrated. To gain insight into this reaction, in situ React IR technology was used to confirm the effectivity and chemoselectivity of this novel Boc reagent. The reaction was carried out chemoselectively in high yield under mild, environment-friendly conditions and was completed quickly within 1 hour. Simultaneously, the Boc carrier was easily recyclable, and has great application prospects for industrial production.
- Du, Fangyu,Zhou, Qifan,Fu, Yang,Zhao, Hanqi,Chen, Yuanguang,Chen, Guoliang
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supporting information
p. 6549 - 6554
(2019/05/04)
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- HETEROCYCLIC COMPOUNDS AS FUNGICIDES
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The present invention relates to novel heterocyclic compound of Formula (I), (I) wherein, Het, L1, A, L2 and R12 are as defined in the detailed description, for use as fungicides.
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Page/Page column 77
(2019/10/01)
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- N-Arylation of Carbamates through Photosensitized Nickel Catalysis
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A highly efficient method of visible light mediated Ni(II)-catalyzed photoredox N-arylation of Cbz-amines/Boc-amines with aryl electrophiles at room temperature is reported. The methodology provides a common access to a wide variety of N-aromatic and N-heteroaromatic carbamate products that find use in the synthesis of several biologically active molecules and provides a distinct advantage over traditional palladium-catalyzed Buchwald reaction.
- Reddy, Leleti Rajender,Kotturi, Sharadsrikar,Waman, Yogesh,Ravinder Reddy, Vudem,Patel, Chirag,Kobarne, Ajinath,Kuttappan, Sasikumar
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p. 13854 - 13860
(2018/10/31)
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- Selective Oxidative Coupling Reaction of Isocyanides Using Peroxide as Switchable Alkylating and Alkoxylating Reagent
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A switchable oxidative coupling reaction of isocyanide and peroxide has been disclosed. In the presence of iron catalyst, the coupling reaction affords N-arylacetamides in good yields. By simply replacing the iron with copper catalyst, another different coupling reaction takes place in which peroxide can serve as alkoxylating source. This protocol represents a new fundamental coupling of two basic chemicals involving C?C and C?O bond-forming process. The unusual reactivity of an isocyano group in a radical reaction acting formally as an amidoyl synthon has also been well established. The experiment outcome reveals that aromatic isocyanides are particularly compatible reaction partners in present coupling reaction, whereas no desired products are observed when aliphatic isocyanides are used. (Figure presented.).
- Zhang, Xinglu,Liu, Zhiqiang,Gao, Yu,Li, Feng,Tian, Yaming,Li, Chunju,Jia, Xueshun,Li, Jian
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supporting information
p. 272 - 277
(2017/11/13)
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- 2-ARYLSULFONAMIDO-N-ARYLACETAMIDE DERIVATIZED STAT3 INHIBITORS
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The present disclosure provides pharmaceutical compositions comprising 2-arylsulfonamido-N-arylacetamide derivatized Stat3 inhibitors and certain pharmaceutically acceptable salts thereof, and methods of their use.
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Paragraph 00425
(2018/08/20)
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- BIFUNCTIONAL COMPOUNDS AND USE FOR REDUCING URIC ACID LEVELS
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Bifunctional compounds that increase uric acid excretion and reduce uric acid production, and monofunctional compounds that either increase uric acid excretion or reduce uric acid production. Methods of using these compounds for reducing uric acid levels
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Paragraph 00145
(2016/12/22)
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- Highly ortho-Selective Chlorination of Anilines Using a Secondary Ammonium Salt Organocatalyst
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An organocatalytic, highly facile, efficient, and regioselective ortho-chlorination of anilines is described. A secondary ammonium chloride salt has been employed as the catalyst and the reaction can be conducted at room temperature without protection from air and moisture. In addition, the reaction is readily scalable and the catalyst can be recycled and reused. This catalytic protocol has been applied to the efficient synthesis of a highly potent c-Met kinase inhibitor. Mechanistic studies revealed that unique structural features of the secondary ammonium chloride salt are important for both the catalysis and regioselectivity of the electrophilic ortho-chlorination.
- Xiong, Xiaodong,Yeung, Ying-Yeung
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supporting information
p. 16101 - 16105
(2016/12/26)
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- Cyanation of unactivated aryl chlorides and aryl mesylates catalyzed by palladium and hemilabile MOP-type ligands
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Palladium-catalyzed cyanation of aryl halides and pseudo halides with potassium hexacyanoferrate is described employing the hemilabile, bulky, and electron-rich MOP-type ligands. When the mixture of t-BuOH and H2O was used as the solvent and K2CO3 as the base, the MOP-type ligands showed high efficiency for the palladium-catalyzed cyanation. The effect of ligand structure was studied in detail, and 2-di-tert-butylphosphino-2′-isopropoxy-1,1′-binaphthyl was the more effective for the cyanation. The catalyst system allows the cyanation of unactivated aryl chlorides, and even aryl mesylates to occur in good yields. Furthermore, the reactivity of different arylated reagents in the catalytic system was found to be: ArBr > ArCl >> ArOMs > ArOSO2Im > ArOSO2NMe2.
- Tu, Yahui,Zhang, Yi,Xu, Sheng,Zhang, Zhaoguo,Xie, Xiaomin
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supporting information
p. 2938 - 2942
(2015/01/16)
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- Silver-catalyzed nitrogenation of alkynes: A direct approach to nitriles through C≡C bond cleavage
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Three in one blow! A novel direct transformation of alkynes into nitriles by a silver-catalyzed nitrogenation reaction through C≡C bond cleavage has been developed. This research provides both a new application for alkynes in organic synthesis, and valuable mechanistic insights into nitrogenation chemistry. Copyright
- Shen, Tao,Wang, Teng,Qin, Chong,Jiao, Ning
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supporting information
p. 6677 - 6680
(2013/07/25)
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- Palladium(II)-catalyzed direct conversion of methyl arenes into aromatic nitriles
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From methyl to nitrile: A mild ammoxidation method, which directly converts methyl arenes into aromatic nitriles, has been developed by using Pd(OAc) 2 and N-hydroxyphthalimide (NHPI) as the catalysts, and tert-butyl nitrite as the nitrogen source and oxidant. Copyright
- Shu, Zhibin,Ye, Yuxuan,Deng, Yifan,Zhang, Yan,Wang, Jianbo
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supporting information
p. 10573 - 10576
(2013/10/21)
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- Per-6-amino-β-cyclodextrin/CuI catalysed cyanation of aryl halides with K4[Fe(CN)6]
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Efficient cyanation of aryl halides is achieved using less toxic K 4[Fe(CN)6] as the reagent and amino-β-cyclodextrins as supramolecular ligands for CuI. Four different amino cyclodextrins viz. per-6-amino-β-CD, per-6-methylamino-β-CD, per-6-butyl-amino-β-CD and mono-6-amino-β-CD are prepared and studied. Aryl and heteroaryl nitriles are obtained in good to excellent yield for even bromo derivatives of flavone and 2-aminopyrans. This system uses catalytic amounts (10 mol%) of both copper iodide and per-6-amino-β-cyclodextrin. Easy separation, the absence of nitrogen atmosphere and excellent yield are the other significant outcomes of this protocol. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
- Azath, Ismail Abulkalam,Suresh, Palaniswamy,Pitchumani, Kasi
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supporting information
p. 2334 - 2339
(2013/01/15)
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- Outer-sphere direction in iridium C-H borylation
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The NHBoc group affords ortho selective C-H borylations in arenes and alkenes. Experimental and computational studies support an outer sphere mechanism where the N-H proton hydrogen bonds to a boryl ligand oxygen. The regioselectivities are unique and com
- Roosen, Philipp C.,Kallepalli, Venkata A.,Chattopadhyay, Buddhadeb,Singleton, Daniel A.,Maleczka, Robert E.,Smith, Milton R.
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supporting information; experimental part
p. 11350 - 11353
(2012/08/29)
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- Pd-catalyzed amidation of aryl(Het) halides with tert-butyl carbamate
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Pd-catalyzed cross-coupling reaction of tert-butyl carbamate with various aryl(Het) halides with Cs2CO3 as base in 1,4-dioxane as solvent was investigated, which resulted in the formation of the desired compounds in moderate to excellent yields.
- Qin, Lijin,Cui, Hongmeng,Zou, Dapeng,Li, Jingya,Wu, Yangjie,Zhu, Zhiwu,Wu, Yusheng
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experimental part
p. 4445 - 4448
(2010/09/12)
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- Amination of aryl iodides using a fluorous-tagged ammonia equivalent
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A fluorous-tagged ammonia equivalent for the Cu-catalyzed amination of aryl iodides is described in which N-Boc-protected anilines are produced in high overall yield and purity. All purification steps are performed using Fluorous SolidPhase Extraction (F-SPE) greatly simplifying and speeding up the isolation of the desired products.
- Nielsen, Simon Dalsgaard,Smith, Garrick,Begtrup, Mikael,Kristensen, Jesper L.
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experimental part
p. 3704 - 3710
(2010/09/05)
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- Room-temperature Pd-catalyzed amidation of aryl bromides using tert-butyl carbamate
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(Chemical Equation Presented) The scope of Pd-catalyzed synthesis of N-Boc-protected anilines from aryl bromides and commercially available tertbutyl carbamate is described. For the first time, this process can be conducted at room temperature (17-22°C) u
- Bhagwanth, Swapna,Waterson, Alex G.,Adjabeng, George M.,Hornberger, Keith R.
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supporting information; experimental part
p. 4634 - 4637
(2009/09/08)
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- INDAZOLE DERIVATIVES
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The invention is concerned with novel indazole derivatives of formula (I) wherein R1, R2, R3, R4, R5, R6, X and Y are as defined in the description and in the claims, as well as physiologic
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Page/Page column 19
(2008/06/13)
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- 6-ARYLALKYLAMINO- 2,3,4,5-TETRAHYDRO-1H-BENZO[D]AZEPINES AS 5-HT2C RECEPTOR AGONISTS
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The present invention provides 6-substituted 2,3,4,5-tetrahydro-lH- benzo[d]azepines of Formula (I) as selective 5-HT2c receptor agonists for the treatment of 5-HT2c associated disorders including obesity, obsessive/compulsive disorder, depression, and anxiety, where, R6 is -NR10R11, where R10 is substituted phenylalkyl or substituted pyridylalkyl and other substituents are as defined in the specification.
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Page/Page column 112
(2010/11/26)
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- Molecular iodine-catalyzed facile procedure for N-Boc protection of amines
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An efficient and practical protocol for the protection of various structurally and electronically divergent aryl and aliphatic amines using (Boc)2O in the presence of a catalytic amount of molecular iodine (10 mol%) under solvent-free conditions at ambient temperature is presented.
- Varala, Ravi,Nuvula, Sreelatha,Adapa, Srinivas R.
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p. 8283 - 8286
(2007/10/03)
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- Copper(II) tetrafluoroborate as a novel and highly efficient catalyst for N-tert-butoxycarbonylation of amines under solvent-free conditions at room temperature
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Commercially available copper(II) tetrafluoroborate hydrate was found to be a highly efficient catalyst for chemoselective N-tert-butoxycarbonylation of amines with di-tert-butyl dicarbonate under solvent-free conditions and at room temperature. Various aromatic amines were protected as their N-tert-butyl carbamates in high yields and in short times. No competitive side reactions such as isocyanate, urea, and N,N-di-t-Boc formation was observed. Chemoselective N-tert-butoxycarbonylation was achieved with substrates bearing OH and SH groups. Chiral α-amino acid esters afforded the corresponding N-t-Boc derivatives in excellent yields.
- Chankeshwara, Sunay V.,Chakraborti, Asit K.
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p. 1087 - 1091
(2007/10/03)
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- Indium(III) halides as new and highly efficient catalysts for N-tert-butoxycarbonylation of amines
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Indium(III) bromide and chloride efficiently catalysed the N-tert-butoxycarbonylation of amines with (Boc)2O at room temperature and under solvent-free conditions. Various aromatic, heteroaromatic and aliphatic amines were converted to N-tert-butylcarbamates in excellent yields in short times. Chiral amines, esters of α-amino acids and β-amino alcohols afforded optically pure N-t-Boc derivatives in high yields. The reactions were chemoselective and no competitive side reactions such as isocyanate, urea, and N,N-di-t-Boc formation were observed. Chemoselective conversion to N-tert-butylcarbamates took place with amino alcohols without any formation of oxazolidinones. Georg Thieme Verlag Stuttgart.
- Chankeshwara, Sunay V.,Chakraborti, Asit K.
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p. 2784 - 2788
(2008/02/05)
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- HIV INHIBITING 1,2,4-TRIAZIN-6-ONE DERIVATIVES
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The present invention relates to HIV replication inhibitors of formula (I) a N-oxide, a pharmaceutically acceptable addition salt, a quaternary amine or a stereochemically isomeric form thereof, wherein ring A and ring B represent phenyl, pyridyl, pyridaz
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Page/Page column 63
(2008/06/13)
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- A novel tert-butoxycarbonylation reagent: 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI)
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The use of 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI) as a tert-butoxycarbonylation reagent for acidic proton-containing substrates such as phenols, aromatic and aliphatic amines hydrochlorides, and aromatic carboxylic acids in the absence of a base is described. The reactions proceed chemoselectively in high yield under mild conditions.
- Saito, Yukako,Ouchi, Hidekazu,Takahata, Hiroki
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p. 11599 - 11607
(2007/10/03)
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- BENZAMIDE DERIVATIVES
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A compound represented by formula (1): wherein X is a single bond or a substituted or unsubstituted lower alkylene group; Z is a saturated or unsaturated monocyclic hydrocarbon ring group or the like; and each of R1, R2, R3 and R4, which may be the same or different, is a hydrogen atom, a halogen atom, a nitro group, a cyano group, a carboxyl group, a substituted or unsubstituted alkyl group, or the like, a prodrug of said compound, or a pharmaceutically acceptable salt of said compound or prodrug has inhibitory effect on Rho kinase and hence is useful for treating diseases which are such that morbidity due to them is expected to be improved by inhibition of Rho kinase and secondary effects such as inhibition of the Na+/H+ exchange transport system caused by the Rho kinase inhibition, for example, hypertension.
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- Antithrombotic compound
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The present invention relates compounds of the formula Aoligosaccharide-spacer-GpIIb/IIIa antagonist wherein the oligosaccharide is a negatively charged oligosaccharide residue comprising four to twenty five monosaccharide units, the charge being compensa
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- Environmentally friendly and efficient: Iron-mediated reduction of 3-methyl-5-aryl-1,2,4-oxadiazoles to benzamidines
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A new synthetic method is described for the mild and selective reduction of 3-methyl-5-aryl-1,2,4-oxadiazoles to amidines employing iron powder in aqueous medium. Its application is demonstrated in the synthesis of 1, a potent and selective urokinase-type plasminogen activator (uPA) inhibitor.
- Sendzik, Martin,Hui, Hon C.
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p. 8697 - 8700
(2007/10/03)
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- Seleno compounds containing nitrone moiety, their preparation and their therapeutic uses
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The present invention provides novel seleno compounds containing nitrone moiety, a process for preparing the same, the use of the novel compounds as therapeutics for treating and/or preventing various medical dysfunctions and diseases arising from reactiv
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- Ag+ mediated deaminations of N-Boc aryl hydrazines for the efficient synthesis of N-Boc aryl amines
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N-Boc-aryl hydrazines were converted into N-Boc-aryl amines under the action of Ag+. Its mild reaction conditions tolerate the presence of a variety of functional groups.
- Lee, Kang-Sang,Lim, Young-Kwan,Cho, Cheon-Gyu
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p. 7463 - 7464
(2007/10/03)
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- Transition metal-catalyzed process for preparing N-aryl amine compounds
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Disclosed is a process for the preparation of N-aryl amine compounds, comprising reacting an amine compound with an arylating compound in the presence of a base and a transition metal catalyst under reaction conditions effective to form an N-aryl amine compound, the transition metal catalyst comprising a Group 8 metal and P(t-Bu)3 as a ligand, and wherein the ratio of the ligand to the Group 8 metal is in the range of about 3:1 to about 0.25:1, and wherein the reaction temperature is less than 100 DEG C. The process of the present invention provides a useful general method of N-arylation for the manufacture of pharmaceuticals, polymers, and the like.
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- Room-temperature palladium-catalyzed amination of aryl bromides and chlorides and extended scope of aromatic C-N bond formation with a commercial ligand
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The reactions of aryl bromides with amines occurs at room temperature when using Pd(0) and P(t-Bu)3 in a 1:1 ratio, and the reactions of aryl chlorides occur at room temperature or 70 °C. The arylation of indoles and the new arylation of carbamates also occur when using P(t-Bu)3 as ligand.
- Hartwig, John F.,Kawatsura, Motoi,Hauck, Sheila I.,Shaughnessy, Kevin H.,Alcazar-Roman, Luis M.
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p. 5575 - 5580
(2007/10/03)
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- Antibody conjugates
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There is disclosed an antibody and antibody-drug conjugate for targeting drug delivery as well as a class of chemicals, termed a drug-binding molecule of complementary structure (csDBM). The csDBM is designed to "fit" the drug by combining multiple non-covalent interactions between functional groups on the drug and opposing functional groups on the csDBM. The net result on the antibody-csDBM-drug conjugate is a drug stably bound to the csDBM so as not to dissociate during in vivo administration, but not so tightly bound to allow drug dissociation from the conjugate without significant loss of activity and retaining the drug's ability to bind to a higher affinity site on or within the target cell.
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