- Dynamic Kinetic Sensitization of β-Dicarbonyl Compounds—Access to Medium-Sized Rings by De Mayo-Type Ring Expansion
-
Herein, we present a photocatalyzed two-carbon ring expansion of β-dicarbonyl compounds with unactivated olefins that provides facile access to medium-sized rings. Selective sensitization of the substoichiometric enol tautomer enables reactivity of substr
- Glorius, Frank,Guldi, Dirk M.,Henkel, Christian,James, Michael J.,Mai, Lukas A.,Paulisch, Tiffany O.,Strieth-Kalthoff, Felix
-
supporting information
(2021/12/27)
-
- Pyrimidine fused ring derivative and application thereof in medicine
-
The invention relates to a compound shown in a general formula (I) or a stereoisomer, a deuterated compound, a solvate, a prodrug, a metabolite, a pharmaceutically acceptable salt or a co-crystal of the compound, an intermediate and a preparation method o
- -
-
Paragraph 0203-0210
(2021/05/12)
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- Palladium Catalyzed Ring Expansion Reaction of Isoxazolones with Isocyanides: Synthesis of 1,3-Oxazin-6-One Derivatives
-
A palladium catalyzed ring expansion reaction of isoxazolones with isocyanides was disclosed. In the reaction, a cascade process involving ring-opening/cyclization was suggested. The reaction features high atomic economy due to no elimination of CO2 occurred. Moreover, products obtained demonstrate aggregation-induced emission properties with relatively high solid-state emission efficiencies. (Figure presented.).
- Zhu, Yi-Ming,Zhang, Wan,Li, Hongkun,Xu, Xiao-Ping,Ji, Shun-Jun
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p. 808 - 818
(2020/12/03)
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- Highly Selective Difluoromethylations of β-Keto Amides with -TMSCF 2Br under Mild Conditions
-
Without employing any transition metal and other additives, efficient methods for selective difluoromethylations of β-keto amides with TMSCF 2 Br reagent have been developed under mild conditions. This protocol allows a convenient access to various α-difluoromethyl β-keto amides with excellent yields (up to 93%) and high carbon/oxygen (C/O) regioselectivities (up to 99:1). The C/O selectivity of β-keto amides could be easily reversed and controlled by simply changing the base. This protocol can be easily scaled-up and the C-difluoromethylation product could be reduced into CF 2 H-containing amino alcohol derivatives. Moreover, the first enantioselective electrophilic difluoromethylation of β-keto amides has been achieved by phase-transfer catalysis.
- Chen, Pengli,Fu, Yang,Hu, Yanqin,Wang, Shuaifei,Wang, Yakun,Zhang, Conghui,Zhang, Mingwei,Zhao, Ting
-
supporting information
p. 1123 - 1130
(2021/06/18)
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- Highly Carbon-Selective Monofluoromethylation of β-Ketoesters with Fluoromethyl Iodide
-
A highly carbon-selective monofluoromethylation of a broad range of β-ketoesters with fluoromethyl iodide under mild conditions is described. The uses of lithium tert-butoxide as the base and diglyme as the solvent made great contributions to the high C/O regioselectivity.
- Ding, Tianqi,Jiang, Lvqi,Yang, Jie,Xu, Yimin,Wang, Guixiang,Yi, Wenbin
-
supporting information
p. 6025 - 6028
(2019/08/20)
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- Lanthanum-Catalyzed Enantioselective Trifluoromethylation by Using an Electrophilic Hypervalent Iodine Reagent
-
A highly enantioselective catalytic method for the synthesis of quaternary α-trifluoromethyl derivatives of 3-oxo esters is described. The reaction uses lanthanum(III) triflate and chiral PyBOX-type C2-symmetric ligands to generate intermediate LaIII complexes that incorporate an enolate moiety of the starting 3-oxo ester and the trifluoromethylation transfer reagent. The enantioselectivity of the reaction stems from the efficient blockage of one of the prochiral faces of the LaIII enolate by one unit of the C2-symmetric ligand.
- Granados, Albert,Rivilla, Iván,Cossío, Fernando P.,Vallribera, Adelina
-
supporting information
p. 8214 - 8218
(2019/05/15)
-
- Construction of Polycyclic β-Ketoesters Using a Homoconjugate Addition/Decarboxylative Dieckmann Annulation Strategy
-
The construction of arene-fused cyclic β-ketoesters from 2-iodoaryl esters and 1,1-cyclopropane diesters is detailed. The synthetic method takes advantage of a CuI·SMe2-mediated homoconjugate addition followed by a decarboxylative Dieckmann cyclization to afford valuable polycyclic building blocks. Various iodoaryl esters and 1,1-cyclopropane diesters were evaluated, and the limitations of both reactions are discussed. Several mechanistic probes are detailed and synthetic applications are described.
- Chen, Zhiwei,Hong, Allen Y.,Linghu, Xin
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p. 6225 - 6234
(2018/05/29)
-
- Iron-Catalyzed Acyl Migration of Tertiary α-Azidyl Ketones: Synthetic Approach toward Enamides and Isoquinolones
-
This paper reports that tertiary α-azidyl phenyl ketones can be transformed into enamides by treatment with FeBr2 at elevated temperature in DMF. The reaction proceeds via 1,2-benzoyl migration from α-carbon to the nitrogen atom, accompanied by expulsion of a nitrogen molecule. This protocol is suitable for the synthesis of N-(cyclopent-1-en-1-yl)benzamides, N-(cyclohex-1-en-1-yl)benzamides, and N-benzoyl-α-methyl enamines and provides a convenient approach toward isoquinolones.
- Yang, Tonghao,Fan, Xing,Zhao, Xiaopeng,Yu, Wei
-
supporting information
p. 1875 - 1879
(2018/04/16)
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- Visible-Light-Mediated Iminyl Radical Generation from Benzyl Oxime Ether: Synthesis of Pyrroline via Hydroimination Cyclization
-
The treatment of an O-(4-methoxybenzyl) oxime ether bearing an olefin substituent and 1-chloroanthraquinone (1-Cl-AQN) catalyst in 2-butanone under visible-light irradiation affords pyrroline via an iminyl radical intramolecular hydroimination. Mechanistic studies indicate that iminyl radical generation mainly proceeds by hydrogen abstraction of the photocatalyst from the benzyl position of the oxime. Moreover, the hydrogen atom was identified in circulation from the benzylic position of the substrates between AQN and 2-butanone to quench the carbon radical without requiring any additional reagents.
- Usami, Kaoru,Yamaguchi, Eiji,Tada, Norihiro,Itoh, Akichika
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supporting information
p. 5714 - 5717
(2018/09/21)
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- Asymmetric Alkynylation of β-Ketoesters and Naphthols Promoted by New Chiral Biphenylic Iodanes
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The preparation of new chiral biphenylic λ3-iodane reagents bearing transferable alkynyl ligands is described. These reagents transfer their carbon-based ligands onto β-ketoesters with an enantiomeric excess (ee) up to 68 %, and most remarkably, enable the dearomative alkynylation of naphthols in good to high yields up to 84 % ee.
- Companys, Simon,Peixoto, Philippe A.,Bosset, Cyril,Chassaing, Stefan,Miqueu, Karinne,Sotiropoulos, Jean-Marc,Pouységu, Laurent,Quideau, Stéphane
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supporting information
p. 13309 - 13313
(2017/10/05)
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- Solvent-Free Synthesis of Salen Ligands and Pd(II)- and Cu(II)-Salen Complexes: Their Use in the Oxidation of α-Tetralones to α-Naphthols
-
Racemic trans -cyclohexane-1,2-diamine was allowed to react with eleven aldehydes with different patterns of substitution at the aromatic ring, in the absence of solvent, by manually milling the reagents. The corresponding imines were obtained in moderated to high chemical yields, in only 10 minutes of reaction. A one-pot, two-step preparation of stable complexes of selected imines with Pd(OAc) 2 and Cu(OAc) 2 and the use of these complexes as catalysts in the aromatization of methyl 1-oxo-1,2,3,4-tetrahydronaphthalene-2-carboxylate to the corresponding methyl 1-hydroxynaphthalene-2-carboxylates, is also reported.
- Cívicos, José F.,Coimbra, Juliana S. M.,Costa, Paulo R. R.
-
supporting information
p. 3998 - 4006
(2017/08/29)
-
- Highly Enantioselective α-Cyanation with 4-Acetylphenyl Cyanate
-
A highly effective asymmetric version of α-cyanation of β-keto esters and amides was developed with a Lewis-acid catalyst. Thus, by using 10 mol % of a tridentate bisoxazoline–zinc(II) complex as the catalyst, a series of chiral nitriles containing a quaternary carbon center were obtained in excellent enantioselectivities (up to 97 % enantiomeric excess) and up to 95 % yield in the presence of 4 ? molar sieve at room temperature. For the first time, mild and active 4-acetylphenyl cyanate was used instead of cyano-hyperiodinate as the cationic cyano source for catalytic asymmetric α-cyanation.
- Qiu, Jia-Shen,Wang, Yao-Feng,Qi, Gui-Rong,Karmaker, Pran G.,Yin, Hong-Quan,Chen, Fu-Xue
-
supporting information
p. 1775 - 1778
(2017/02/15)
-
- Enantioselective electrophilic cyanation of β-keto amides catalysed by a cinchona organocatalyst
-
An operationally simple protocol for the enantioselective electrophilic α-cyanation of β-keto amides catalyzed by cinchona-derived catalysts has been demonstrated. The resulting products could be obtained with good to high enantioselectivities (up to 88% ee) and with excellent yields (up to 94%) by employing the mild active 4-acetylphenyl cyanate as the cationic cyano source in the catalytic asymmetric α-cyanation reaction.
- Karmaker, Pran Gopal,Qiu, Jiashen,Wu, Di,Reng, Mengmeng,Yang, Zhuo,Yin, Hongquan,Chen, Fu-Xue
-
supporting information
p. 7753 - 7757
(2017/10/06)
-
- Copper-Catalysed Decarboxylative Trifluoromethylation of β-Ketoacids
-
An efficient method for Cu-catalyzed decarboxylative trifluoromethylation of β-ketoacids to achieve α-trifluoromethyl ketones was developed. A wide variety of synthetically useful α-trifluoromethyl ketones were obtained in modest to good yields under mild reaction conditions. The present method also exhibits good functional-group compatibility.
- Xu, Xiaolan,Chen, Huanhuan,He, Jianbo,Xu, Huajian
-
supporting information
p. 1665 - 1668
(2017/10/05)
-
- 2,4-Diaminopyrimidines as dual ligands at the histamine H1 and H4 receptor - H1/H4-receptor selectivity
-
Distinct diaminopyrimidines, for example, 4-(4-methylpiperazin-1-yl)-5,6-dihydrobenzo[h]quinazolin-2-amine are histamine H4 receptor (H4R) antagonists and show high affinity to the H4R, but only a moderate affinity to the
- Hammer, Sebastian G.,Gobleder, Susanne,Naporra, Franziska,Wittmann, Hans-Joachim,Elz, Sigurd,Heinrich, Markus R.,Strasser, Andrea
-
supporting information
p. 292 - 300
(2016/01/09)
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- Copper- versus palladium-catalyzed aromatization of 2-(methoxycarbonyl) tetralones: Synthesis of methyl 1-hydroxy-2-naphthoates
-
The aromatization of α-tetralones substituted at the β-position by an ester group is reported using either CuI or Pd2(dba)3. In the case of using CuI (10 mol %) as catalyst and Cs2CO3 as base in dioxane, 2-(methoxycarbonyl)-α-tetralones are smoothly converted into the corresponding methyl 1-hydroxy-2-naphthoates at 70 °C under air. Alternatively, Pd2(dba)3 (1.25 mol %) can also be used as catalyst in the presence of K3PO4 as base in toluene also at 70 °C under argon. These are the most straightforward methodologies for the aromatization of these types of α-tetralones. CuI is the catalyst of choice due to higher efficiency, economical and practical reasons.
- Cívicos, José F.,Ribeiro, Carlos M.R.,Costa, Paulo R.R.,Nájera, Carmen
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p. 1897 - 1902
(2016/04/05)
-
- An approach to (±)-Lingzhiol
-
(±)-Lingzhiol has been synthesized from commercially available 5,8-dimethoxytetralone in seven steps with an overall yield of 10.3% via an unprecedented acid-catalyzed semipinacol-type rearrangement. In addition, a novel strategy for the construction of the tetracyclic 5/5/6/6 core structure of lingzhiol has been developed via a tandem rearrangement/reduction/lactonization reaction.
- Li, Xiaoyu,Liu, Xiaoyu,Jiao, Xiaozhen,Yang, Hongguang,Yao, Yangyang,Xie, Ping
-
supporting information
p. 1944 - 1946
(2016/05/19)
-
- 5-AMINO-4-CARBAMOYL-PYRAZOLE COMPOUNDS AS SELECTIVE AND IRREVERSIBLE T790M OVER WT-EGFR KINASE INHIBITORS AND USE THEREOF????
-
Disclosed are compounds of Formula (I), pharmaceutical compositions comprising the same, processes for the preparation thereof, and the use thereof.
- -
-
Paragraph 0176
(2016/03/13)
-
- Cooperative Indium(III)/Silver(I) System for Oxidative Coupling/Annulation of 1,3-Dicarbonyls and Styrenes: Construction of Five-Membered Heterocycles
-
A cooperative indium(III)/silver(I) system for the synthesis of various five-membered heterocycles, including dihydrofurans, pyrroles, spirolactones, and spiroiminolactones, through the sequential oxidative coupling/annulation reaction of 1,3-dicarbonyl compounds with styrenes has been developed. Four different heterocyclic systems were successfully synthesized depending on the substitution pattern of the substrates using readily available starting materials. This system has the advantages of a broad substrate scope, moderate to good chemical yields, an operationally easy and simple procedure, and short reaction times. (Figure presented.) .
- Ko, Tae Yun,Youn, So Won
-
supporting information
p. 1934 - 1941
(2016/07/06)
-
- Trimethylchlorosilane-Mediated Mild α-Chlorination of 1,3-Dicarbonyl Compounds Promoted by Phenyliodonium Diacetate
-
Trimethylchlorosilane was used as chlorine source for the α-chlorination of 1,3-dicarbonyl compounds with phenyliodonium diacetate as oxidant at room temperature. The reaction allows the selective synthesis of α-monochlorinated products from different kinds of 1,3-dicarbonyl compounds in good yield. The potential possibility of this conversion for bromination has also been investigated.
- Chong, Siying,Su, Yingpeng,Wu, Lili,Zhang, Weigang,Ma, Junyan,Chen, Xiaowei,Huang, Danfeng,Wang, Ke-Hu,Hu, Yulai
-
supporting information
p. 1359 - 1370
(2016/05/02)
-
- New Monocyclic, Bicyclic, and Tricyclic Ethynylcyanodienones as Activators of the Keap1/Nrf2/ARE Pathway and Inhibitors of Inducible Nitric Oxide Synthase
-
A monocyclic compound 3 (3-ethynyl-3-methyl-6-oxocyclohexa-1,4-dienecarbonitrile) is a highly reactive Michael acceptor leading to reversible adducts with nucleophiles, which displays equal or greater potency than the pentacyclic triterpenoid CDDO in inflammation and carcinogenesis related assays. Recently, reversible covalent drugs, which bind with protein targets but not permanently, have been gaining attention because of their unique features. To explore such reversible covalent drugs, we have synthesized monocyclic, bicyclic, and tricyclic compounds containing 3 as an electrophilic fragment and evaluated them as activators of the Keap1/Nrf2/ARE pathway and inhibitors of iNOS. Notably, these compounds maintain the unique features of the chemical reactivity and biological potency of 3. Among them, a monocyclic compound 5 is the most potent in these assays while a tricyclic compound 14 displays a more robust and specific activation profile compared to 5. In conclusion, we demonstrate that 3 is a useful electrophilic fragment for exploring reversible covalent drugs. (Chemical Equation Presented).
- Li, Wei,Zheng, Suqing,Higgins, Maureen,Morra, Rocco P.,Mendis, Anne T.,Chien, Chih-Wei,Ojima, Iwao,Mierke, Dale F.,Dinkova-Kostova, Albena T.,Honda, Tadashi
-
supporting information
p. 4738 - 4748
(2015/06/30)
-
- Electrophilic trifluoromethylthiolation of carbonyl compounds
-
A general method for the α-trifluoromethylthiolation of carbonyl compounds, without prefunctionalization, has been developed. Aldehydes, ketones, esters, amides, keto-esters, alkaloids, and steroids have been trifluoromethylthiolated with good yields. This work, proposing a new reagent for electrophilic trifluoromethylthiolation, provides a route towards the original synthesis of various trifluoromethylthiolated molecules for further applications.
- Alazet, Sebastien,Zimmer, Luc,Billard, Thierry
-
supporting information
p. 8589 - 8593
(2014/07/21)
-
- TREATING DIABETES WITH DIPEPTIDYL PEPTIDASE-IV INHIBITORS
-
The present invention is directed to novel substituted dihydropyrrolopyrazoles of structural Formula I which are inhibitors of the dipeptidyl peptidase-N enzyme and which are useful in the treatment or prevention of diseases in which the dipeptidyl peptid
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-
Page/Page column 35
(2014/02/16)
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- A new mild method for the C-acylation of ketone enolates. a convenient synthesis of β-keto-esters,-thionoesters, and-thioesters
-
A new method for ketone enolate C-acylation is described which utilizes alkyl pentafluorophenylcarbonates, thiocarbonates, and thionocarbonates as the reactive acylating agents, and MgBr2·Et2O, DMAP, and i-Pr2NEt as the reagents for enolization. A wide range of ketones have been observed to undergo clean C-acylation via this protocol.
- Hale, Karl J.,Grabski, Milosz,Flasz, Jakub T.
-
supporting information
p. 370 - 373
(2013/03/13)
-
- HETEROCYCLIC COMPOUNDS FOR THE INHIBITION OF PASK
-
Disclosed herein are new heterocyclic compounds and compositions and their application as pharmaceuticals for the treatment of disease. Methods of inhibiting PAS Kinase (PASK) activity in a human or animal subject are also provided for the treatment of diseases such as diabetes mellitus.
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-
Page/Page column 19
(2012/11/08)
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- COMPOUND HAVING HETERO RING SKELETON, AND PROCESS FOR PRODUCING OPTICALLY ACTIVE COMPOUND USING THE AFOREMENTIONED COMPOUND AS ASYMMETRIC CATALYST
-
The present invention provides a compound having a heterocyclic skeleton, which is represented by of the formula (I) : wherein R1 and R2 are the same or different and each is a lower alkyl group optionally having substituent(s), an a
- -
-
Page/Page column 27
(2012/03/08)
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- Potent and selective adenosine A2A receptor antagonists: [1,2,4]-triazolo[4,3-c]pyrimidin-3-ones
-
Antagonism of the adenosine A2A receptor affords a possible treatment of Parkinson's disease. In the course of investigating pyrazolo[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine A2A antagonists, we prepared [1,2,4]-triazolo[4,3-c]pyrimidi
- Harris, Joel M.,Neustadt, Bernard R.,Zhang, Hongtao,Lachowicz, Jean,Cohen-Williams, Mary,Varty, Geoff,Hao, Jinsong,Stamford, Andrew W.
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scheme or table
p. 2497 - 2501
(2011/05/15)
-
- Direct displacement of alkoxy groups of vinylogous esters by grignard reagents
-
The direct displacement of alkoxy groups from the β position of aromatic and unsaturated esters and ketones is described. The reaction is chemo- and regioselective, displaying wide substrate scope.
- Brockway, Anthony J.,González-López, Marcos,Fettinger, James C.,Shaw, Jared T.
-
supporting information; experimental part
p. 3515 - 3518
(2011/06/24)
-
- Delineating origins of stereocontrol in asymmetric Pd-catalyzed α-hydroxylation of 1,3-ketoesters
-
Systematic studies of reaction conditions and subsequent optimization led to the identification of important parameters for stereoselectivity in the asymmetric α-hydroxylation reaction of 1,3-ketoesters. Enantioselectivities of up to 98% can be achieved for cyclic substrates and 88% for acyclic ketoesters. Subsequently, the combination of cyclic/acyclic ketoester, catalyst, and oxidant was found to have a profound effect on reaction rates and turnover-limiting steps. The stereochemistry of the reaction contradicts that observed for other similar electrophilic substitution reactions. This was rationalized by transition-state modeling, which revealed a number of cooperative weak interactions between oxidant, ligand, and counterion, together with C-H/π interactions that cumulatively account for the unusual stereoselectivity.
- Smith, Alexander M. R.,Rzepa, Henry S.,White, Andrew J. P.,Billen, Denis,Hii, King Kuok
-
supporting information; experimental part
p. 3085 - 3096
(2010/07/17)
-
- 1,2,4-TRIAZOLO[4,3-C]PYRIMIDIN-3-ONE AND PYRAZOLO [4,3-E] -1,2,4-TRIAZOLO [4,3-C] PYRIMIDIN-3-ONE COMPOUNDS FOR USE AS ADENOSINE A2A RECEPTOR ANTAGONISTS
-
Compounds of the Formula I wherein R1 and R2 together with the carbon atoms to which they are bonded optionally form a further heteroaromatic ring of the formula (II) as well as pharmaceutically acceptable salts, solvates, esters and
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-
Page/Page column 36
(2009/10/22)
-
- MACROCYCLIC BENZOFUSED PYRIMIDINE DERIVATIVES
-
Macrocyclic benzofused pyrimidine compounds, compositions comprising such compounds, methods for making the compounds, and methods of treating and preventing the progression of diseases, conditions and disorders using such compounds and compositions are described herein.
- -
-
Page/Page column 145-146
(2008/12/05)
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- Enantioselective decarboxylation of β-keto esters with Pd/amino alcohol systems: Successive metal catalysis and organocatalysis
-
The kinetics and mechanisms of one-pot cascade reactions of racemic β-keto esters to give chiral ketones in the presence of Pd/C-chiral amino alcohol catalyst systems were studied. Transformation of 2-methyl-l-tetralone-2- carboxylic acid benzyl ester (1) into 2-methyl-1-tetralone (4) in the presence of Pd/C and cinchona alkaloids or ephedrine was chosen as a model reaction. After the first reaction step, the Pd-catalysed dehenzylation of 1 to afford the corresponding β-keto acid (2), there are two possible reaction routes that may be catalysed by the chiral amino alcohol in solution or by Pd0 sites on the metal surface in co-operation with the adsorbed amino alcohol. The reaction intermediate 2 was synthesized, and the kinetics of decarboxylation were followed by NMR, UV and IR spectroscopy. The studies revealed that the role of Pd is to trigger the reaction series by deprotection of 1. The subsequent dominant reaction route from the racemic β-keto acid 2 to the chiral ketone 4 is catalysed by the chiral amino alcohol in the liquid phase. It is shown that kinetic resolution of the diastereomeric salt of rac-2 and the chiral amino alcohol plays a key role in the enantioselection. High enantioselectivity necessitates an amino alcohol/rac-2 ratio of at least 2. A high ratio favours the formation of 1:1 amino alcohol/acid diastereomeric complexes, and the second amino alcohol molecule may be responsible for the enantioselective protonation of 2 in the diastereomeric complex.
- Kukula, Pavel,Matousek, Vaclav,Mallat, Tamas,Baiker, Alfons
-
supporting information; experimental part
p. 2699 - 2708
(2009/06/17)
-
- Rotationally constrained 2,4-diamino-5,6-disubstituted pyrimidines: A new class of histamine H4 receptor antagonists with improved druglikeness and in vivo efficacy in pain and inflammation models
-
A new structural class of histamine H4 receptor antagonists (6-14) was designed based on rotationally restricted 2,4-diaminopyrimidines. Series compounds showed potent and selective in vitro H4 antagonism across multiple species, goo
- Cowart, Marlon D.,Altenbach, Robert J.,Liu, Huaqing,Hsieh, Gin C.,Drizin, Irene,Milicic, Ivan,Miller, Thomas R.,Witte, David G.,Wishart, Neil,Fix-Stenzel, Shannon R.,McPherson, Michael J.,Adair, Ronald M.,Wetter, Jill M.,Bettencourt, Brian M.,Marsh, Kennan C.,Sullivan, James P.,Honore, Prisca,Esbenshade, Timothy A.,Brioni, Jorge D.
-
experimental part
p. 6547 - 6557
(2009/10/09)
-
- Highly enantioselective synthesis of β-amino acid derivatives by the lewis base catalyzed hydrosilylation of β-enamino esters
-
A study was conducted to demonstrate highly enantioselective synthesis of β-amino acid derivatives by the Lewis base catalyzed hydrosilylation of βenamino esters. It was found that these catalyst and its analogue displayed excellent activities and enantioselectivities in promoting hydrosilylation of N-aryl β-enamino esters. N-picolinoylpyrrolidine derivatives and N-picolioylephedrine were also evaluated in hydrosilylation of (Z)-methyl 3-phenyl-3-(phenylamino)acrylate. The generality of the Lewis base organocatalyzed hydrosilylation of various β-enamino esters were examined under the optimized conditions. It was observed that the catalytic system exhibited a high sensitivity to the N-substituents, while all the N-aryl β-enamino esters underwent the hydrosilylation smoothly to give corresponding β-amino esters.
- Zheng, Hong-Jie,Chen, Wen-Bing,Wu, Zhi-Jun,Deng, Jin-Gen,Lin, Wen-Qing,Yuan, Wei-Cheng,Zhang, Xiao-Mei
-
supporting information; experimental part
p. 9864 - 9867
(2009/10/02)
-
- Studies on the intramolecular cyclizations of bicyclic δ- hydroxynitriles promoted by triflic anhydride
-
(Chemical Equation Presented) Studies have been conducted to investigate the reactivity of several bicyclic δ-hydroxynitriles with triflic anhydride in dichloromethane. The reactions of the analogues derived from 1-indanone and 1-tetralone lead to annulat
- Justribo, Valeria,Pellegrinet, Silvina C.,Colombo, Maria I.
-
p. 3702 - 3712
(2008/02/04)
-
- Structural effects in the Pd-induced enantioselective deprotection-decarboxylation of β-ketoesters
-
Structural effects in the chiral base and the influence of some key reaction parameters (catalyst type and solvent) in the Pd-induced enantioselective decarboxylation (cascade reaction) of three different α,α-disubstituted benzyl β-ketoesters were explored. The reaction intermediate after debenzylation (β-keto-carboxylic acid) was synthesized and its decarboxylation studied independently. The highest ee (up to 60%) in the cascade reaction was achieved with those substrates that contained an aromatic ring system and with chiral amino alcohols that possessed an extended aromatic ring (quinine and quinidine). Polar solvents with weak H-bond donor and acceptor properties favor enantioselection.
- Kukula, Pavel,Matousek, Vaclav,Mallat, Tamas,Baiker, Alfons
-
p. 2859 - 2868
(2008/09/17)
-
- BENZENESULFONYL-CHROMANE, THIOCHROMANE, TETRAHYDRONAPHTHALENE AND RELATED GAMMA SECRETASE INHIBITORS
-
This invention discloses novel gamma secretase inhibitors of the formula: R2 and R3, or R2 and R4, or R3 and R4, together with the atoms to which they are bound, can form a fused cycloalkyl
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-
Page/Page column 73
(2010/11/28)
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- Lewis acid-promoted α-hydroxy β-dicarbonyl to α-ketol ester rearrangement
-
The decarbomethoxylation reaction of a substituted α-hydroxy-α-carbomethoxy pentacyclic substituted ketone, used as an advanced intermediate in the synthesis of the alkaloid aspidophytine, can be effected by heating with MgI2 in CH3CN. The reaction was shown to proceed by a novel α-hydroxy β-dicarbonyl to α-ketol ester rearrangement. It was possible to isolate a carbonate intermediate in 75% yield, thereby providing support for the proposed pathway.
- Hong, Xuechuan,Mejía-Oneto, José M.,Padwa, Albert
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p. 8387 - 8390
(2007/10/03)
-
- An Expedient Synthesis of Benzo[h]quinazolin-4(3H)-one: Structure of Samoquasine A Revisited
-
An expedient four-step synthesis of benzo[h]quinazolin-4(3H)-one (1) starting from 1-tetralone is reported. The claimed identity of samoquasine A with perlolidine (4) has been discussed in the light of the present synthesis.
- Chakrabarty, Manas,Sarkar, Sandipan,Harigaya, Yoshihiro
-
p. 2292 - 2294
(2007/10/03)
-
- Pyrrolidine and thiazole derivatives with metallo-beta-lactamase inhibitory properties
-
A method of treatment of bacterial infections in humans or animals which comprises administering, in combination with a β-lactam antibiotic, a therapeutically effective amount of an amino acid derivative or a pharmaceutically acceptable salt, solvate or i
- -
-
-
- Studies on New Acidic Azoles as Glucose-Lowering Agents in Obese, Diabetic db/db Mice
-
Bioisosteric substitution was used as a tool to generate several new structural alternatives to the thiazolidine-2,4-dione and tetrazole heterocycles as potential antidiabetic agents.Among the initial leads that emerged from this strategy, a family of aci
- Kees, Kenneth L.,Caggiano, Thomas J.,Steiner, Kurt E.,Fitzgerald, John J.,Kates, Michael J.,et al.
-
p. 617 - 628
(2007/10/02)
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- Epoxidation with Dioxiranes derived from 2-Fluoro-2-substituted-1-tetralones and -1-indanones
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Homochiral 2-fluoro-2-substituted-1-tetralones (10a, 10b, 13) and ethyl 2-fluoro-1-indanone-2-carboxylate (16) have been isolated.The dioxirane derivatives of these ketones have been prepared in situ, and have been shown to epoxidise alkenes but not enantioselectively.The dioxirane derivative of methyl 2,5,7-trifluoro-1-indanone-2-carboxylate (18) has been shown to be comparatively efficient in epoxidation.
- Brown, David S.,Marples, Brian A.,Smith, Paul,Walton, Lesley
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p. 3587 - 3606
(2007/10/02)
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- Short and efficient access to β-ketoamides
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β-Ketoamides are obtained in good yields either through a photochemical rearrangement of diazodiketones or by aminolysis of β-ketoesters. photolysis / Wolff rearrangement / ketoketene / β-ketoesters / aminolysis /4-(dimethylamino)pyridine / β-ketoamides
- Cossy, Janine,Belotti, Damien,Bouzide, Abderahim,Thellend, Annie
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p. 723 - 729
(2007/10/02)
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- Synthesis of conformationally restricted relatives of the mevinic acids
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Condensations between the tricyclic ketones 9, 19 and 23 and the sodio-lithio dianion of methyl acetoacetate lead to the conformationally restricted Mevinic acid relatives 12b, 20b and 26 respectively, following lactonization and selective reduction. The approach of the nucleophile is stereospecific in the first two instances but not in the last; explanations for this behaviour are given. The target compounds showed negligible HMGCoA reductase antagonism.
- Bennett, Frank,Fenton, Garry,Knight, David W.
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p. 5147 - 5158
(2007/10/02)
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- Acylketene acetals in organic synthesis
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The preparation and reactivity of achiral and enantiomerically pure acylketene acetals are described. The key reactions of these substrates involve facile conjugate hydroboration and organolithium addition. Enantiomerically pure acylketene acetals were employed to generate a homochiral β-keto ketal through a highly diastereoselective lithium enolate quench. This β-ketal, which was also prepared through a desymmetrization ketalization reaction on a meso dione, was employed in the synthesis of the insect pheromone sitophilure.
- Eid Jr.,Konopelski
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p. 975 - 992
(2007/10/02)
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- Intramolecular photocyclizations of amino ketones to form fused and bridged bicyclic amines
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The irradiation of cyclic aminoketones produces bicyclic amines derived from intramolecular electron transfer followed by cyclization.
- Kraus, George A.,Chen, Li
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p. 7151 - 7154
(2007/10/02)
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- Arylmagnesium Bromide Additions to 1-Tetralone-2-acetic Acid Followed by Catalytic Hydrogenolysis: Stereochemical Consequences
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A Stork reaction route (7 -> 1b) was utilized to synthesize 1-tetralone-2-acetic acid methyl ester (1a) from 1-tetralone.Addition of a 2'-(o-methoxyphenyl)magnesium bromide to this ketone followed by palladium-catalyzed hydrogenation of the intermediate cis lactones (2, verified by X-ray crystal structure determination of 2a, Figure 1), afforded predominantly a 1,2-cis tetralin (3) accompanied by smaller yields of the corresponding 1,2-trans tetralin (4).The stereochemical consequences of this reaction sequence was unequivocally established by X-ray crystal structure elucidation of 1,2-cis methyl ester 3b (Figure 2) and 1,2-trans carboxylic acid 4a (Figure 3).Stereochemical assignments for the analogous diastereoisomeric sets 3c-f and 4c-f were obtained by high-field (400-MHz) 1H and 13C NMR correlations with the crystal structures.The overall reaction pathway illustrates a useful approach to 1,2-cis-alkylated tetralins and certain sterically hindered 1,2-trans-alkylated tetralins.
- Djerassi, Carl,Pettit, George R.,Herald, Delbert L.,Sanson, Dale R.
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p. 5360 - 5368
(2007/10/02)
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- A Practical Synthetic Method for β-Ketosters from Ketones
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A practical, simple, one-pot synthesis of β-ketoesters (3) from ketones (1) via bis(methylthio)ketene acetals (4) was achieved. Keywords---β-ketoester; bis(methylthio)ketene acetals; C-alkoxycarbonylation; ketone; carbon disulfide
- Tomozane, Hideo,Takeuchi, Yasuo,Yamato, Masatoshi
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p. 401 - 404
(2007/10/02)
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