cas 5292-43-3, tert-Butyl bromoacetate | Articles data

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Visible-Light-Induced Oxidative α-Alkylation of Glycine Derivatives with Ethers under Metal-Free Conditions
In this work, a visible-light-induced oxidative α-alkylation of glycine derivatives with ethers has been developed in the presence of catalytic Eosin Y. Under the blue light of a 3 W LED, a range of α-etherized glycine derivatives, including α-amino esters, α-amino ketones and α-amino amides, were achieved with good to excellent yields and functional group tolerance with tert-butyl hydroperoxide (TBHP) as oxidant at ambient temperature. The operationally easy procedure provides an economical, metal-free, and mild alternative for the synthesis of the α-etherized glycine derivatives.
Song, Yang,Zhang, Hao,Guo, Jiabao,Shao, Yifei,Ding, Yuzhou,Zhu, Li,Yao, Xiaoquan
p. 5914 - 5921
(2021/11/22)

Acridine Orange Hemi(Zinc Chloride) Salt as a Lewis Acid-Photoredox Hybrid Catalyst for the Generation of α-Carbonyl Radicals
A readily accessible organic-inorganic hybrid catalyst is reported for the reductive fragmentation of α-halocarbonyl compounds. The robust hybrid catalyst is a self-stabilizing combination of ZnCl2 Lewis acid and acridine orange as the photoactive organic dye. Mechanistic specifics of this hybrid catalyst have been studied in detail using both photophysical and electrochemical experiments. A systematic study enabled the discovery of the appropriate Lewis acid for the effective LUMO stabilization of α-halocarbonyl compounds and thereby lowering of reduction potential within the range of a standard organic dye. This strategy resolves the issues like dehalogenative hydrogenation or homo-coupling of alkyl radicals by guiding the photoredox cycle through an oxidative quenching pathway. The cooperativity between the photoactive organic dye and the Lewis acid counterparts empowers functionalization with a wide range of coupling partners through efficient and controlled generation of alkyl radicals and serves as an appropriate alternative to the expensive late transition metal-based photocatalysts. To demonstrate the application potential of this cooperative catalytic system, four different synthetic transformations of α-carbonyl bromides were explored with broad substrate scopes.
Das, Sanju,De Sarkar, Suman,Mandal, Tanumoy
supporting information

(2021/12/10)

Synthesis, antiinflammatory activity, and molecular docking studies of bisphosphonic esters as potential MMP-8 and MMP-9 inhibitors
Bisphosphonic acids (or bisphosphonates) have been successfully used in the clinic treatment of bone diseases for over decades. Additionally, the antiinflammatory activity of these compounds has been gaining attention. In our previous work, we synthesized and in vivo evaluated the bisphosphonic esters 1 and 2, finding a moderate edema inhibition upon oral and topical administration on BALB/c mice. Thus, in this work, the bioisosteric replacement of an amide functional group for an ester afforded the new bisphosphonates 3–6, which had a moderate oral edema inhibition (25 mg/kg dose) and a significant topical antiinflammatory activity (2 mg/ear) on BALB/c mice, with 6 being the most active hit (55.9% edema inhibition), comparable to the positive control (55.5% edema inhibition) on a TPA topical model. Next, to assess the acute toxicity of the synthesized derivatives, test animals were administered with 50–100 mg/kg of 3–6, respectively, by an oral route, and after 14 days, neither lethality nor a significative weight loss were observed. Finally, a structure–activity relationship (SAR) and a molecular docking analysis of 3–6 helped us to explain the trend observed in biological tests. Considering all these aspects, we propose the inhibition of MMP-8 and MMP-9 as a possible action mechanism of the synthesized derivatives.
Cortes-Pacheco, Abimelek,Jiménez-Arellanes, María Adelina,Juárez-Vázquez, María del Carmen,López-Torres, Adolfo,Palacios-Can, Francisco José,Ramírez-Marroquín, Oscar Abelardo,Razo-Hernández, Rodrigo Said,Valcarcel-Gami?o, José Antonio
supporting information
p. 1277 - 1287
(2020/07/10)

A Tunable Route to Prepare α,β-Unsaturated Esters and α,β-Unsaturated-γ-Keto Esters through Copper-Catalyzed Coupling of Alkenyl Boronic Acids with Phosphorus Ylides
A tunable strategy to prepare α,β-unsaturated esters and α,β-unsaturated-γ-keto esters in good to excellent yields was developed through copper-catalyzed oxidative coupling of phosphorus ylides with alkenyl boronic acids under mild conditions. The reaction without water afforded α,β-unsaturated esters, ketones, and amides while α,β-unsaturated-γ-keto esters, 1,4-α,β-unsaturated diketones and α,β-unsaturated-γ-keto amides were obtained when using 5.0 equiv. of water. H2O18 labeling experiments showed that water played an important role in the formation of α,β-unsaturated-γ-keto esters. A plausible formation mechanism for α,β-unsaturated esters and α,β-unsaturated-γ-keto esters was proposed based on mechanistic studies. Phosphonium salts could also be used directly as coupling partners instead of phosphorus ylides. The reaction exhibited a broad substrate scope, good functional group tolerance, good regioselectivity, and diverse coupling products. (Figure presented.).
Bi, Hong-Yan,Liu, Feng-Ping,Liang, Cui,Su, Gui-Fa,Mo, Dong-Liang
supporting information
p. 1510 - 1516
(2018/03/05)

In situ generation of nitrile oxides from copper carbene and tert -butyl nitrite: Synthesis of fully substituted isoxazoles
Herein, we present a novel [3 + 2] cycloaddition reaction of β-keto esters with nitrile oxides, which were generated in situ from copper carbene and tert-butyl nitrite. This three-component reaction provides new methodology for the direct synthesis of fully substituted isoxazole derivatives, featuring mild reaction conditions, readily accessible starting materials and simple operation. The experimental studies and DFT calculations suggest that the reaction starts with the generation of the key intermediate nitrile oxides, followed by a [3 + 2] cycloaddition reaction of β-keto esters to give the final isoxazole products.
Chen, Rongxiang,Ogunlana, Abosede Adejoke,Fang, Shangwen,Long, Wenhao,Sun, Hongmei,Bao, Xiaoguang,Wan, Xiaobing
supporting information
p. 4683 - 4687
(2018/07/06)

In Situ Generation of Oxazole Ylide and Interception with Sulfonamide: Construction of Amidines Using Two Diazo Molecules
A novel generation of oxazole ylide and interception with sulfonamide have been well developed to construct fully substituted amidines. This copper-catalyzed four-component reaction incorporates two diazo molecules to target amidines and shows broad substrate scope, excellent functional groups tolerance and good to excellent yields.
Chen, Jijun,Long, Wenhao,Zhao, Yanwei,Li, Haiyan,Zheng, Yonggao,Lian, Pengcheng,Wan, Xiaobing
supporting information
p. 857 - 865
(2018/07/31)

Interception of Radicals by Molecular Oxygen and Diazo Compounds: Direct Synthesis of Oxalate Esters Using Visible-Light Catalysis
The synthesis of oxalate esters through a radical process, rather than the traditional ionic reaction, has been well developed in which the radicals induced by visible light are trapped by molecular oxygen and diazo compounds under room temperature. This reaction is operationally simple, mild, and shows broad substrate scopes in α-bromo ketones and diazo compounds.
Ma, Meihua,Hao, Weiwei,Ma, Liang,Zheng, Yonggao,Lian, Pengcheng,Wan, Xiaobing
supporting information
p. 5799 - 5802
(2018/09/12)

Synthesis of Kainoids and C4 Derivatives
A unified stereoselective synthesis of 4-substituted kainoids is reported. Four kainic acid analogues were obtained in 8-11 steps with up to 54% overall yields. Starting from trans-4-hydroxy-l-proline, the sequence enables a late-stage modification of C4 substituents with sp2 nucleophiles. Stereoselective steps include a cerium-promoted nucleophilic addition and a palladium-catalyzed reduction. A 10-step route to acid 21a was also established to enable ready functionalization of the C4 position.
Tian, Zhenlin,Menard, Frederic
p. 6162 - 6170
(2018/05/23)

Photoinduced Intermolecular [4+2] Cycloaddition Reaction for Construction of Benzobicyclo[2.2.2]octane Skeletons
A novel and efficient method for the synthesis of highly substituted benzobicyclo[2.2.2]octane skeletons has been explored. Under UV-light irradiation, o-divinylbenzenes underwent a pericyclic reaction to form the cyclic o-quinodimethane intermediates which were subsequently reacted with olefins through [4+2] addition to construct the benzobicyclo[2.2.2]octane skeletons in mild conditions. Gram scale reactions demonstrated the synthetic potential application of this protocol.
Liu, Qiang,Wang, Junlei,Li, Dazhi,Yang, Chao,Xia, Wujiong
p. 1389 - 1402
(2017/02/10)

Cycloaddition of Fluorenone N-Aryl Nitrones with Methylenecyclopropanes and Sequential 1,3-Rearrangement: An Entry to Synthesis of Spirofluorenylpiperidin-4-ones
A facile synthesis of various spirofluorenylpiperidin-4-ones has been achieved in good yields from fluorenone N-aryl nitrones and methylenecyclopropanes. This method involved an initial cycloaddition to form a 5-spirocyclopropane-isoxazoline, which underwent a highly selective 1,3-rearrangement to give the desired product. The stereochemistry of the spirofluorenylpiperidin-4-one could be controlled by the cycloaddition and sequential rearrangement strategy. Furthermore, the spirofluorenylpiperidin-4-ones could be not only prepared in one-pot procedure but also converted to useful scaffolds by reduction or oxidation conditions.
Ma, Xiao-Pan,Zhu, Jie-Feng,Wu, Si-Yi,Chen, Chun-Hua,Zou, Ning,Liang, Cui,Su, Gui-Fa,Mo, Dong-Liang
p. 502 - 511
(2017/04/26)

A green synthetic method for tert-butyl bromoacetate
The invention relates to a green synthetic method for tert-butyl bromoacetate. The method is characterized in that bromoacetic acid and isobutylene are adopted as raw materials in the method, a solid superacid is adopted as a catalyst, and the method includes performing an acid-ester esterification reaction at room temperature under atmospheric pressure in an organic solvent, performing filtration after the reaction is finished to recover the catalyst, distilling filtrate to recover the solvent and distilling to obtain the tert-butyl bromoacetate the content of which is 99.0% or above. The reaction yield is 95% or above. The method is high in yield, good in product quality, low in cost, simple in reaction process operation, basically free of generation of three wastes, low in environment pollution, high in operation safety and suitable for industrial production. The catalyst is easily available and can be used repeatedly.
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Paragraph 0011; 0012

(2017/02/28)

Phosphine-Catalyzed Domino β/γ-Additions of Benzofuranones with Allenoates: A Method for Unsymmetrical 3,3-Disubstituted Benzofuranones
A phosphine-catalyzed domino process of benzofuranones with allenoates has been developed which furnishes highly functionalized unsymmetrical 3,3-disubstituted benzofuranones in synthetically useful yields. The mechanism for the transformation is a tandem β-umpolung/γ-umpolung process.
Huang, Zhusheng,Yang, Xiuqin,Yang, Fulai,Lu, Tao,Zhou, Qingfa
supporting information
p. 3524 - 3527
(2017/07/17)

Asymmetric addition of arylboronic acids to glyoxylate catalyzed by a ruthenium/Me-BIPAM complex
The enantioselective synthesis of α-hydroxy esters by ruthenium-catalyzed 1,2-addition of arylboronic acids to tert-butyl glyoxylate is described. The use of RuCl2(PPh3)3 with (R,R)-Me-BIPAM gave optically active mandelic acids of up to 99% ee. Addition of a fluoride salt such as potassium fluoride (KF) or caesium fluoride (CsF) was effective for achieving high enantioselectivities. The Royal Society of Chemistry 2012.
Yamamoto, Yasunori,Shirai, Tomohiko,Miyaura, Norio
supporting information; experimental part
p. 2803 - 2805
(2012/04/23)

Cross-dehydrogenative coupling reactions by transition-metal and aminocatalysis for the synthesis of amino acid derivatives
The direct approach: The title coupling reactions of N-aryl glycine esters with unmodified ketones occurred smoothly in the presence of tert-butyl hydroperoxide (TBHP) or 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) under mild conditions (see scheme). The oxidant used for C-H activation determined the selectivity of the reactions for a particular type of ketone substrate. Copyright
Xie, Jin,Huang, Zhi-Zhen
supporting information; experimental part
p. 10181 - 10185
(2011/02/27)

Microwave-assisted solvent-free intramolecular 1,3-dipolar cycloaddition reactions leading to hexahydrochromeno[4,3-b]pyrroles: scope and limitations
We report the microwave-assisted solvent-free synthesis of hexahydrochromeno[4,3-b]pyrroles. Intramolecular 1,3-dipolar cycloadditions proceed under these conditions within 15-40 min in 16-84% yields. An influence of the microwave irradiation upon various [3+2] cycloaddition reaction intermediates was studied. Additionally, a scope and limitations of these reactions including an influence of the dipolarophile geometry upon the cycloaddition selectivity and steric demands of the dipole upon its reactivity were also disclosed. These observations led us to postulate a preferable transition state of the reaction. Finally, an influence of the microwave irradiation to the isomerization of activated olefins was also described.
Pospí?il, Ji?í,Potá?ek, Milan
p. 337 - 346
(2007/10/03)

5-Hydroxy[1,2]oxazinan-3-ones as potential carbapenem and D-ala-D-ala surrogates
The title compounds are amino acids whose nitrogen atom is enclosed in a six-membered cyclic hydroxamate bearing a C5-hydroxyl group. They belong to a proposed new family of antibacterial agents targeted to the penicillin receptor. The glycine and alanine members of the family have been synthesized, as racemates, in seven steps from the four-carbon synthon diketene and the tert-butyl esters of N-hydroxyglycine and N-hydroxyalanine. Numerous alternatives to diketene have also been examined, but these lead mainly to five-membered cyclic hydroxamates. The theoretical considerations that have led to this synthetic programme are discussed in some detail. They include analysis of the structures of natural and unnatural penicillin surrogates, analysis of the penicillin pharmacophore, and a treatment of the chemical reaction with which penicillin blocks bacterial cell wall synthesis. The glycine derivative exhibits marginal but real activity vs. Micrococcus luteus. The alanine derivative, which more closely resembles D-ala-D-ala, is fifty times more active. Two five-membered structural isomers of the glycine derivative are inactive.
Wolfe, Saul,Akuche, Christiana,Ro, Stephen,Wilson, Marie-Claire,Kim, Chan-Kyung,Shi, Zheng
p. 915 - 936
(2007/10/03)

Preparation and Characterization of [5-13C]-(2S,4R)-Leucine and [4-13C]-(2S,3S)-Valine - Establishing Synthetic Schemes to Prepare Any Site-Directed Isotopomer of L-Leucine, L-Isoleucine and L-Valine
In this paper a chemo-enzymatic method has been developed that gives access to any isotopomer of the essential amino acids isoleucine and valine. The method gives the correct introduction of the second chiral center in (2S,3S)-isoleucine and allows for discrimination between the two prochiral methyl groups in valine as shown by the preparation of (2S,3S)-[4- 13C] valine. For the preparation of (2S)-leucine in any isotopomeric form, the O'Donnell method to prepare optically active amino acids has been used. The protected glycine scaffold used in this method has been prepared by a strategy that allows access to any isotopomeric form. The preparation of [5-13C]-(2S,4R)-leucine shows that the O'Donnell method in combination with the Evans method to obtain chiral 2-methylpropyl iodide leads to a good discrimination between the two prochiral methyl groups. The O'Donnell strategy for the preparation of α-amino acids is preferred over other methods since the reaction conditions are mild, the chiral auxiliary can be easily recovered and the optically active product can be easily separated. For the preparation of isotopically enriched valine and isoleucine the O'Donnell method is not suitable, because the alkyl substituents involved have a secondary halide substituent which is sterically too hindered to give an effective reaction with the protected glycine. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
Siebum, Arjan H. G.,Woo, Wei Sein,Lugtenburg, Johan
p. 4664 - 4678
(2007/10/03)

Scavenger assisted combinatorial process for preparing libraries of tertiary amine compounds
This invention relates to a novel solution phase process for the preparation of tertiary amine combinatorial libraries. These libraries have utility for drug discovery and are used to form wellplate components of novel assay kits.
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(2008/06/13)

A Mild and Efficient Alumina-Promoted Synthesis of t-Butyl Esters
A wide variety of aliphatic acid chlorides including an optically active one has been efficiently converted to their t-butyl esters under very mild reaction conditions by employing activated alumina as a catalyst.
Nagasawa, Kazuo,Yoshitake, Shinji,Amiya, Takao,Ito, Keiichi
p. 2033 - 2040
(2007/10/02)

SYNTHESIS OF SOME FUNCTIONALIZED PHOSPHINOCARBOXYLIC ACIDS
Various functionalized phosphinocarboxylic acids have been prepared by a number of complementary methods.Reactions of relatively electron-poor secondary phosphides with electron-rich halocarboxylates in liquid ammonia give high yields of phosphinocarboxylates.The substitution reactionmay proceed by a classical SN2 mechanism or by an SN rad mechanism.Reduction of the carboxilate can be a deleterious side reaction in the preparation of phosphinoacetic acids.Several phosphinopropionic acids are prepared by the Michael adition of diphenylphosphine to unsaturated esters.A valuable method proved to be the reaction of dichlorophosphinoacetic ester with functionalized organometallic reagents. Key words: Phosphine; carboxylic acid; ligand; functionalized; synthesis; NMR data.
van Doorn, J. A.,Meijboom, N.
p. 211 - 222
(2007/10/02)

A NEW METHOD FOR THE PREPARATION OF TERTIARY BUTYL ETHERS AND ESTERS
T-butyl 2,2,2-trichloroacetimidate (1), readily prepared by addition of t-butanol to trichloroacetonitrile, is an efficient reagent for the preparation of t-butyl ethers and esters in the presence of a catalytic amount of boron trifluoride etherate.
Armstrong, Alan,Brackenridge, Ian,Jackson, Richard F.W.,Kirk, Joanna M.
p. 2483 - 2486
(2007/10/02)

Chemistry of Cumulenes, 6. Syntheses and Reactions of 1-H-Allene-1,3-dicarboxylic Acid Monoesters
The title compounds 5a-e have been prepared.The carboxylation of allene monoesters 4 was successful with the phenyl derivative 4a only.The resulting extremely unstable halfester 5a as its benzylammonium salt was spontaneously transformed into the enamine ester 7.The alkyl-substituted allenes 5b-e are accessible via Wittig reaction of alkylmalonic monoester chlorides 11 with (alkoxycarbonyl)methylene ylides 12, which comprise the 2,2,2-trichloroethyl or the tert-butyl residues as selectively cleavable carboxylic protecting groups.Cleavage of the CCl3CH2 group with Zn succeeded for the tert-butylallenes 13a/b only.In the case of the methylallene 13c the cleavage was accompanied by hydrogenation of the allene.The mechanism of this reaction is discussed.Cleavage of the tert-butyl ester group in 13d and e was readily achieved with ether/sulfuric acid.
Nader, Franz W.,Brecht, Angelika,Kreisz, Siegfried
p. 1196 - 1207
(2007/10/02)

SYNTHESE DE DIENES-1,4 FONCTIONNALISES PAR ADDITION DE ZINCIQUES ALLYLIQUES FONCTIONNALISES SUR DES ALCYNES VRAIS ET LEUR CYCLISATION EN HETEROCYCLES OU CARBOCYCLES
The regiospecific addition of functionalized allylic bromides to terminal alkynes in the presence of zinc furnishes a great variety of highly functionalized 1,4-dienes with moderate to good yields.The synthetic utility of these 1,4-dienes is demonstrated by various cyclization reactions leading to an α-methylene-γ-butyrolactone, to 3,5-difunctionalized piperidines, to a cyclic triester and to 6- or 7-membered phosphorus heterocyclic compounds.
Knochel, P.,Normant, J. F.
p. 1 - 24
(2007/10/02)

Antihypertensive amides
Compounds of the structure: STR1 wherein R1, R2, R3, R4, R5, and R6 are hydrogen, alkyl, alkenyl, alkynyl, phenyl-alkyl, or cycloalkyl, n is an integer from 0 to 4 inclusive, M is heterocyclic or heterocyclic alkyl, Y is hydroxy, alkoxy, amino, or substituted amino, amino-alkanoyl, aryloxy, aminoalkoxy, or hydroxyalkoxy, and R7 is hydrogen, alkanoyl, carboxylalkanoyl, hydroxyalkanoyl, amino-alkanoyl, cyano, amidino, carbalkoxy, ZS, or STR2 wherein Z is hydrogen, alkyl, hydroxyalkyl, aminoalkyl or the radical STR3 wherein R1, R2, R3, R4, R5, R6, n, M and Y are as described above; and where Y is hydroxy their nontoxic, pharmaceutically acceptable alkali metal, alkaline earth metal, and amine salts.
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(2008/06/13)

Antihypertensive amides
Compounds of the structure: STR1 wherein R1, R2, R3, R4, R5, and R6 are hydrogen, alkyl, alkenyl, alkynyl, phenyl-alkyl, or cycloalkyl, n is an integer from 0 to 4 inclusive, M is alkenyl, alkynyl, cycloalkyl, cycloalkyl-alkyl, polycycloalkyl, polycyclo-alkyl-alkyl, aryl, aralkyl, heteroaryl, heteroaryl-alkyl, hetero-cycloalkyl, hetero-cycloalkyl-alkyl, alkoxyalkyl, alkylthioalkyl, alkylamino-alkyl, dialkylamino-alkyl, fused aryl-cycloalkyl, fused aryl-cycloalkyl-alkyl, fused heteroaryl-cycloalkyl, or fused heteroaryl-cycloalkyl-alkyl, Y is hydroxy, alkoxy, amino, or substituted amino, aminoalkanoyl, aryloxy, aminoalkoxy, or hydroxyalkoxy, and R7 is hydrogen, alkanoyl, carboxylalkanoyl, hydroxyalkanoyl, amino-alkanoyl, cyano, amidino, carbalkoxy, ZS, or STR2 wherein Z is hydrogen, alkyl, hyroxyalkyl, aminoalkyl or the radical STR3 wherein R1, R2, R3, R4, R5, R6, n, M and Y are as described above; and where Y is hydroxy their non-toxic, pharmaceutically acceptable alkali metal, alkaline earth metal, and amine salts.
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(2008/06/13)

Antihypertensive amides
Compounds of the structure: STR1 wherein R1, R2, R3, R4, R5, and R6 are hydrogen, alkyl, alkenyl, alkynyl, phenyl-alkyl, or cycloalkyl, n is an integer from 0 to 4 inclusive, M is heterocyclic or heterocyclic alkyl, Y is hydroxy, alkoxy, amino, or substituted amino, amino-alkanoyl, aryloxy, aminoalkoxy, or hydroxyalkoxy, and R7 is hydrogen, alkanoyl, carboxylalkanoyl, hydroxyalkanoyl, amino-alkanoyl, cyano, amidino, carbalkoxy, ZS, or STR2 wherein Z is hydrogen, alkyl, kydroxyalkyl, aminoalkyl or the radical STR3 wherein R1, R2, R3, R4, R5, R6, n, M and Y are as described above; and where Y is hydroxy their nontoxic, pharmaceutically acceptable alkali metal, alkaline earth metal, and amine salts.
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(2008/06/13)