- Convenient and inexpensive synthesis of (1R,2R)-trans-1-amino-6-nitroindan- 2-ol
-
Racemic trans-1-amino-6-nitroindam-2-ol (rac-1) has been prepared in five steps from inexpensive indene (7) in 96% overall yield. The key step was a direct nitration of the known trans-1-aminoindan-2-ol (rac-9) which gave sulfuric acid mono-(rac-trans-1-amino-6-nitroindan-2-yl) ester (rac-10) in quantitative yield. The latter was quantitatively converted into rac-1 by treatment with aqueous 6 N HCl and then ammonia solutions. The same transformations of (1R,2R)-9 [prepared by deracemization of rac-9 with (-)-dibenzoyl-L-tartaric acid (DBT)] proceeded without loss of the optical activity. Deracemization of rac-1 applying (+)-(5)-L-mandelic acid (MA) furnished (1R,2R)-1 and (1s,2s)-1 in 34 and 17% yield, respectively, with e.e. ≥ 98 and 97.6%, respectively. Procedures for recycling of the chiral auxiliaries DBT and MA are also described. The structures of key intermediates were confirmed by X-ray crystal structure analysis.
- Kozhushkov, Sergei I.,Yufit, Dmitrii S.,De Meijere, Armin
-
-
Read Online
- Hydrogen bonding of hydroxy groups to carbanions in indenide and fluorenide derivatized alcohols directly observed by UV, IR, and NMR spectroscopy
-
For investigation of hydrogen bonding to carbanions a number of carbanions containing hydroxy groups have been designed and synthesized. The carbanions were of the type R′-CR2-CHR-CR2-OH, with R′ being an indenide or a fluorenide group and R a methyl group or a hydrogen, and were generated from the corresponding indenes and fluorenes. Intramolecular hydrogen bonding was observed by UV, IR, and NMR spectroscopy in both polar [dimethyl sulfoxide (DMSO) and tetrahydrofuran (THF)] and apolar (benzene and toluene) non-hydrogen bond donor solvents with properly designed carbanions. In the latter solvents cryptand 211 was used for complexation of the counter Li+ cation. For some derivatives the presence of both intramolecular hydrogen bonding to the carbanion and intermolecular hydrogen bonding of the hydroxy group to the solvent was observed. The UV spectroscopy indicated the perturbation of the proton accepting carbanion and IR and NMR spectroscopy showed the effect of the hydrogen bonding on the proton donating OH group.
- Mc Ewen, Ian,R?nnqvist, Mats,Ahlberg, Per
-
-
Read Online
- Synthesis of poly(indene carbonate) from indene oxide and carbon dioxide - A polycarbonate with a rigid backbone
-
The catalytic coupling of carbon dioxide with indene oxide utilizing (salen)Co(III)-2,4-dinitrophenoxide in the presence of an onium salt is presented. X-ray structural data for indene oxide monomer as well as cisindene carbonate display near planarity of the fused cyclopentene and benzene rings. Low temperature (0 °C) is required to selectively afford copolymer vs cyclic carbonate from the coupling reactions of CO2 and indene oxide. The produced poly(indene carbonate) samples have molecular weights of up to 7100 Da, with corresponding glass transition temperatures of up to 134 °C, the highest yet reported for polycarbonates produced from CO2/epoxides coupling. Poly(indene carbonate) is thermally stable up to 249 °C. The polymerizations are well controlled, with PDI values ≤1.3.
- Darensbourg, Donald J.,Wilson, Stephanie J.
-
-
Read Online
- Synthesis of new indanyl nucleoside analogues and their biological evaluation on hepatitis C virus (HCV) replicon
-
Here, we report a convenient synthetic procedure for the preparation of four novel indanyl carbanucleoside derivatives in the racemic form. The action of these compounds against hepatitis C virus was evaluated in vitro using the replicon cell line, Huh7.5 SG. Contrary to our expectations, all these compounds did not inhibit, but rather promoted HCV genotype 1b (HCVg1b) replication. Similar effects have been reported for morphine in the replicon cell lines, Huh7 and Huh8. Several biological experiments and computational studies were performed to elucidate the effect of these compounds on HCVg1b replication. Based on all the experiments performed, we propose that the increase in HCVg1b replication could be mediated, at least in part, by a similar mechanism to that of morphine on the enhancement of this replication. The presence of opioid receptors in Huh7.5 SG cells was indirectly determined for the first time in this work.
- Gómez, Matías E.,Gentile, Emiliano A.,Florencia Martini,Cuestas, María L.,Mathet, Verónica L.,Moltrasio, Graciela Y.,Moglioni, Albertina G.
-
-
Read Online
- From simple organobromides or olefins to highly value-added bromohydrins: A versatile performance of dimethyl sulfoxide
-
A novel and efficient direct transformation of secondary bromides or olefins to highly value-added bromohydrins has been disclosed. Dimethyl sulfoxide (DMSO), a cheap and common solvent, performs its versatile role as a solvent, an essential oxidant, and also as an oxygen source in this bromohydrin synthesis.
- Song, Song,Huang, Xiaoqiang,Liang, Yu-Feng,Tang, Conghui,Li, Xinwei,Jiao, Ning
-
-
Read Online
- The absolute configuration of 2-bromo-2,3-dihydro-1H-inden-1-ols
-
All four possible stereoisomers of cis- and trans-2-bromo-2,3-dihydro-1H-inden-1-ols, which are important intermediates in the synthesis of biologically active compounds, were synthesized and their configurations were studied by enzymatic kinetic resoluti
- Prysiazhnuk, Dmitry V.,Rusanov, Eduard B.,Kolodiazhnyi, Oleg I.
-
supporting information
p. 3023 - 3031
(2021/08/13)
-
- Electrochemical bromofunctionalization of alkenes in a flow reactor
-
The bromination of organic molecules has been extensively studied to date, yet there is still a demand for safe and sustainable methodologies. Hazardous reagents, selectivity, low atom economy and waste production are the most persisting problems of brominating reagents. The electrochemical oxidation of bromide to bromine is a viable strategy to reduce waste by avoiding chemical oxidants. Furthermore, thein situgeneration of reactive intermediates minimizes the risk of hazardous reagents. In this work, we investigate the electrochemical generation of bromine from hydrobromic acid in a flow electrochemical reactor. Various alkenes could be converted to their corresponding dibromides, bromohydrines, bromohydrin ethers and cyclized products in good to excellent yields.
- Seitz, Jakob,Wirth, Thomas
-
supporting information
p. 6892 - 6896
(2021/08/20)
-
- Concurrent Formation of N-H Imines and Carbonyl Compounds by Ruthenium-Catalyzed C-C Bond Cleavage of β-Hydroxy Azides
-
A commercial cyclopentadienylrutenium dicarbonyl dimer ([CpRu(CO)2]2) efficiently catalyzes the formation of N-H imines and carbonyl compounds simultaneously from β-hydroxy azides via C-C bond cleavage under visible light. Density functional theory calculations for the cleavage reaction support the mechanism involving chelation of alkoxy azide species and liberation of nitrogen as the driving force. The synthetic utility of the reaction was demonstrated by a new amine synthesis promoted by chemoselective allylation of imine and synthesis of isoquinoline.
- Lee, Jeong Min,Bae, Dae Young,Park, Jin Yong,Jo, Hwi Yul,Lee, Eunsung,Rhee, Young Ho,Park, Jaiwook
-
supporting information
p. 4608 - 4613
(2020/06/05)
-
- Oxidative β-Halogenation of Alcohols: A Concise and Diastereoselective Approach to Halohydrins
-
β-Halohydrins bearing transformable halo- and hydroxyl groups, are easily converted into various valuable blocks in organic and pharmaceutical synthesis. A diastereoselective β-halogenation of benzylic alcohols was achieved under simple and low-cost conditions, which provided a direct synthesis of β-halohydrins. The simple reaction conditions, easily available reagents, high diastereoselectivities, and additional oxidant-free make this reaction very attractive and practical.
- Ai, Lingsheng,Wang, Weijin,Wei, Jialiang,Li, Qing,Song, Song,Jiao, Ning
-
p. 437 - 441
(2019/02/26)
-
- Bromination of olefins with HBr and DMSO
-
A simple and inexpensive methodology is reported for the conversion of alkenes to 1,2-dibromo alkanes via oxidative bromination using HBr paired with dimethyl sulfoxide, which serves as the oxidant as well as cosolvent. The substrate scope includes 21 olefins brominated in good to excellent yields. Three of six styrene derivatives yielded bromohydrins under the reaction conditions.
- Karki, Megha,Magolan, Jakob
-
p. 3701 - 3707
(2015/04/22)
-
- I2O5-mediated bromohydroxylation and dibromination of olefins using KBr in water
-
An efficient and green bromohydroxylation and dibromination of various olefins mediated by I2O5 has been developed in this work. A series of olefins gave the corresponding α-bromo-alcohols and dibromides as the major products using KBr as the brominating reagent in aqueous medium at room temperature. The diastereo- and regio-selectivities are extremely high.
- Wang, Yajun,Wang, Jinxi,Xiong, Yun,Liu, Zhong-Quan
-
supporting information
p. 2734 - 2737
(2014/05/06)
-
- BNBTS More than brominating agent: Green and one-pot route for the C-N bond formation in water from alkenes
-
In this paper, in addition to introducing efficient method for bromohydrin and bromoether preparation, simple, green and efficient method to C-N bond formation from alkene and N,N'-Dibromo-N,N'-1,2-ethanediyl- bis(ptoluenesulfonamide) [BNBTS] in water was investigated. The reaction between alkenes, β-cyclodexterin, and BNBTS took place in water afterward, by making media basic; it will give the corresponding valuable building blocks in good yields (45-79%).
- Kazemi, Foad,Kakroudi, Mazaher Abdollahi
-
p. 500 - 504
(2013/08/25)
-
- Regio-and stereoselective hydroxybromination and dibromination of olefins using ammonium bromide and oxone
-
An efficient protocol for the synthesis of vicinal bromohydrins and dibromides from olefins is presented. Various olefins are regio-and stereoselectively hydroxybrominated and dibrominated with anti fashion, following Markonikov's rule, using eco-friendly, non-toxic, and stable reagents such as NH4Br and oxone in CH3CN/H2O (1:1) and CH3CN without employing catalyst in moderate to excellent yields. Bromohydrins are formed instantaneously.
- MacHarla, Arun Kumar,Chozhiyath Nappunni, Rohitha,Nama, Narender
-
supporting information; experimental part
p. 1401 - 1405
(2012/04/04)
-
- Addition of halide to π-bond directly from aqueous NaX solution: A general strategy for installation of two different functional groups
-
Activation of π-bond with organic Lewis acid and cationic surfactant mediated direct transfer of halides to alkyne and alkene are demonstrated to afford α,α-dihaloketones and other valuable synthons with outstanding selectivities.
- Pandit, Palash,Gayen, Krishnanka S.,Khamarui, Saikat,Chatterjee, Nirbhik,Maiti, Dilip K.
-
supporting information; experimental part
p. 6933 - 6935
(2011/08/06)
-
- Organocatalysis in the stereoselective bromohydrin reaction of alkenes
-
An efficient regio- and stereo-selective (>99:1) trans-bromohydrination (bromohydroxylation and bromomethoxylation) of alkenes including α,β-unsaturated carbonyl compounds with N-bromosuccinimide (NBS) has been achieved by using 1.0 mol% of N,N'-diarylthi
- Bar, Sukanta
-
experimental part
p. 605 - 612
(2010/08/21)
-
- Epoxidation of olefins by β-bromoalkoxydimethylsulfonium ylides
-
Olefins can be converted to their respective epoxides in a one-pot procedure by dissolving the olefin in anhydrous DMSO, adding NBS to the reaction mixture to generate a β-bromoalkoxydimethylsulfonium ylide, and then adding DBU to the reaction mixture. A large variety of alkenes were successfully epoxi-dized with yields largely dependent on the structure of the alkene. Most importantly, the facial selectivity of this one-pot process is the opposite of that observed when using traditional epoxidizing reagents. Electron-poor alkenes are not epoxidized under these conditions.
- Majetich, George,Shimkus, Joel,Li, Yang
-
supporting information; experimental part
p. 6830 - 6834
(2011/03/18)
-
- Mechanism of the enantioselective oxidation of racemic secondary alcohols catalyzed by chiral Mn(III)-salen complexes
-
The experiments described here clarify the mechanism and origin of the enantioselectivity of the oxidation of racemic secondary alcohols catalyzed by chiral Mn(III)-salen complexes using HOBr, Br2/H2O/KOAc or PhI(OAc)2/H2O/KBr as a stoichiometric oxidant. Key points of the proposed pathway include (1) the formation of a Mn(V)-salen dibromide, (2) its subsequent reaction with the alcohol to give an alkoxy-Mn(V) species, and (3) carbonyl-forming elimination to produce the ketone via a highly organized transition state with intramolecular transfer of hydrogen from carbon to an oxygen of the salen ligand.
- Brown, M. Kevin,Blewett, Megan M.,Colombe, James R.,Corey
-
supporting information; experimental part
p. 11165 - 11170
(2010/10/03)
-
- Functionalisation of indene
-
Dibromo- and tribromoindane were synthesised by bromination of indene. Treatment of dibromo- and tribromoindane with various silver salts (silver acetate, perchlorate, sulfate and nitrate) in different solvents opened up an entry to the synthesis of various di- and tri-substituted indane derivatives.
- Tutar, Ahmet,Cakmak, Osman,Balci, Metin
-
p. 507 - 511
(2007/10/03)
-
- Green approach for the conversion of olefins into vic-halohydrins using N-halosuccinimides in ionic liquids
-
Alkenes undergo smooth bromo- and iodohydroxylation with N-bromo- and N-iodosuccinimides/water, respectively, using the air and moisture stable ionic liquid [bmim]BF4 as a novel recyclable reaction medium in high to quantitative yields. N-Halosuccinimides show enhanced reactivity in ionic liquids thereby reducing the reaction times and improving the yields considerably.
- Yadav,Reddy,Baishya, Gakul,Harshavardhan,Janardhana Chary,Gupta, Manoj Kumar
-
p. 3569 - 3572
(2007/10/03)
-
- NaIO4-Mediated Selective Oxidative Halogenation of Alkenes and Aromatics Using Alkali Metal Halides
-
(Equation presented) NaIO4 oxidizes alkali metal halides efficiently in aqueous medium to halogenate alkenes and aromatics and produce the corresponding halo derivatives in excellent regio and stereoselectivity. The system also demonstrates the asymmetric version of bromo hydroxylation using β-cyclodextrin complexes, resulting in moderate ee.
- Dewkar, Gajanan K.,Narina, Srinivasarao V.,Sudalai, Arumugam
-
p. 4501 - 4504
(2007/10/03)
-
- Asymmetric transfer hydrogenation of ketones using amino alcohol and monotosylated diamine derivatives of indane
-
A series of 1,2-amino alcohol and 1,2-monotosylated diamine derivatives of indane have been applied as ligands in the asymmetric ruthenium(II)-catalysed transfer hydrogenation reaction of a series of ketones. Of these, the cis-1-aminoindan-2-ol derivative gives some of the highest asymmetric inductions reported for any amino alcohol ligand in this application.
- Palmer, Matthew J.,Kenny, Jennifer A.,Walsgrove, Tim,Kawamoto, Aparecida M.,Wills, Martin
-
p. 416 - 427
(2007/10/03)
-
- Lipase-mediated resolution of trans-1-azidoindan-2-ol: A new route to optically pure cis-1-aminoindan-2-ol
-
Optically pure trans-1-azidoindan-2-ol has been prepared in both enantiomeric forms via lipase-mediated kinetic transesterification in organic solvent. A route to optically pure cis-1-aminoindan-2-ol has also been developed by using the optically pure trans-azidoalcohol thus obtained.
- Takahashi, Michiyasu,Ogasawara, Kunio
-
p. 954 - 958
(2007/10/03)
-
- The Synthesis and Chemistry of 4-Aza-azulene
-
4-Aza-azulene and its 5-bromo and 6-methoxy derivatives have been efficiently synthesized by spray pyrolysis of 2-halogenoindan-1-yl azidoformates at 300 deg C and 1-2 mm pressure of nitrogen.Bromination of 4-aza-azulene gives 1-bromo, 3-bromo, and 1,3-di
- Meth-Cohn, Otto,Moore, Clive,Rooyen, Petrus H. van
-
p. 1793 - 1802
(2007/10/02)
-
