cas 1674-30-2, (+/-)-2-CHLORO-1-PHENYLETHANOL

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In Situ Formation and Reactions of Chloromethyl-lithium under Sonochemical Conditions
Under sonication, bromochloromethane, a carbonyl compound, and lithium in tetrahydrofuran yield the corresponding α-chlorohydrin, which can cyclise to the epoxide, in excellent yields.
Einhorn, Cathy,Allavena, Corinne,Luche, Jean-Louis
p. 333 - 334
(1988)
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Catalytic Meerwein-Pondorf-Verley reduction by simple aluminum complexes
(matrix presented) Catalytic MPV reduction was successfully carried out using simple aluminum precatalysts. Alkylaluminum reagents were converted to a low-aggregation aluminum alkoxide that was highly active for the MPV reduction of several carbonyl substrates in high yield (50-99%) using iPrOH as the reducing agent. A high degree of cisftrans selectivity was achieved in the reduction of 2-methylcyclohexanone (cis/trans = 20/80) by iPrOH. When chiral hydride sources were utilized in the reduction of 2-chloroacetophenone, high enantioselectivity (68-80% ee) was observed.
Campbell, E. Joseph,Zhou, Hongying,Nguyen, SonBinh T.
p. 2391 - 2393
(2001)
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Dihydroxylation of styrene by sodium chlorite with scandium triflate
Dihydroxylation of styrene by chlorite (ClO2 ?) with scandium triflate [Sc(OTf)3] occurs efficiently to produce 1-phenylethane-1,2-diol under the ambient conditions. Scandium triflate acting as a strong Lewis acid is found to accelerate the disproportionation of ClO2 ? to produce ClO? and ClO3 ?. A scandium-chlorine dioxide complex (Sc3+ClO2 ?) is generated by the reaction of ClO? with ClO2 ? in the presence of Sc3 +. The binding of Sc3 + to ClO2 ? was detected by the electron paramagnetic resonance measurements, enhancing the reactivity and selectivity of styrene hydroxylation.
Ohkubo, Kei,Hirose, Kensaku,Shibata, Takekatsu,Takamori, Kiyoto,Fukuzumi, Shunichi
(2017)
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Enantioselective ring-opening of epoxides by HF-reagents: Asymmetric synthesis of fluoro lactones
The asymmetric ring opening of meso- and racemic-epoxides with different HF-reagents mediated by enantiopure (salen)chromium chloride provides optically active fluorohydrins with maximum 90% e.e. This reaction as well as lipase-catalyzed deracemization of
Haufe, Günter,Bruns, Stefan,Runge, Martina
p. 55 - 61
(2001)
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A phosphonium ylide as a visible light organophotoredox catalyst
A phosphonium ylide-based visible light organophotoredox catalyst has been designed and successfully applied to halohydrin synthesis using trichloroacetonitrile and epoxides. An oxidative quenching cycle by the ylide catalyst was established, which was confirmed by experimental mechanistic studies.
Toda, Yasunori,Tanaka, Katsumi,Matsuda, Riki,Sakamoto, Tomoyuki,Katsumi, Shiho,Shimizu, Masahiro,Ito, Fuyuki,Suga, Hiroyuki
supporting information
p. 3591 - 3594
(2021/04/14)

Chiral aminoalcohols and squaric acid amides as ligands for asymmetric borane reduction of ketones: Insight to in situ formed catalytic system by DOSY and multinuclear NMR experiments
A series of squaric acid amides (synthesized in 66–99% isolated yields) and a set of chiral aminoalcohols were comparatively studied as ligands in a model reaction of reduction of α-chloroacetophenone with BH3?SMe2. In all cases, the aminoalcohols demonstrated better efficiency (up to 94% ee), while only poor asymmetric induction was achieved with the corresponding squaramides. A mechanistic insight on the in situ formation and stability at room temperature of intermediates generated from ligands and borane as possible precursors of the oxazaborolidine-based catalytic system has been obtained by1H DOSY and multinuclear 1D and 2D (1H,10/11B,13C,15N) NMR spectroscopy of equimolar mixtures of borane and selected ligands. These results contribute to better understanding the complexity of the processes occurring in the reaction mixture prior to the possible oxazaborolidine formation, which play a crucial role on the degree of enantioselectivity achieved in the borane reduction of α-chloroacetophenone.
Dobrikov, Georgi M.,Nikolova, Yana,Petkova, Zhanina,Shestakova, Pavletta
supporting information

(2021/11/27)

Dynamic Kinetic Resolution of Alcohols by Enantioselective Silylation Enabled by Two Orthogonal Transition-Metal Catalysts
A nonenzymatic dynamic kinetic resolution of acyclic and cyclic benzylic alcohols is reported. The approach merges rapid transition-metal-catalyzed alcohol racemization and enantioselective Cu-H-catalyzed dehydrogenative Si-O coupling of alcohols and hydrosilanes. The catalytic processes are orthogonal, and the racemization catalyst does not promote any background reactions such as the racemization of the silyl ether and its unselective formation. Often-used ruthenium half-sandwich complexes are not suitable but a bifunctional ruthenium pincer complex perfectly fulfills this purpose. By this, enantioselective silylation of racemic alcohol mixtures is achieved in high yields and with good levels of enantioselection.
Oestreich, Martin,Seliger, Jan
supporting information
p. 247 - 251
(2020/10/29)

CeO2-nanocubes as efficient and selective catalysts for the hydroboration of carbonyl groups
The CeO2-nanoparticle catalysed hydroboration of carbonyl compounds with HBpin (pin = OCMe2CMe2O) is reported to afford the corresponding borate esters in excellent yield. A series of aromatic and aliphatic aldehydes and ketones having synthetically important functional groups were well-Tolerated under mild reaction conditions. Further, chemoselective hydroboration of aldehydes over other reducible functional groups such as ketone, nitrile, hydroxide, alkene, alkyne, amide, ester, nitro, and halides was achieved. Importantly the catalyst can be recycled up to ten runs with slight loss in activity. This journal is
Bhawar, Ramesh,Bose, Shubhankar Kumar,Patil, Kiran S.
p. 15028 - 15034
(2021/09/04)

Organomagnesium Based Flash Chemistry: Continuous Flow Generation and Utilization of Halomethylmagnesium Intermediates
The generation of highly unstable chloromethylmagnesium chloride in a continuous flow reactor and its reaction with aldehydes and ketones is reported. With this strategy, chlorohydrins and epoxides were synthesized within a total residence time of only 2.6 s. The outcome of the reaction can be tuned by simply using either a basic or an acidic quench. Very good to excellent isolated yields, up to 97%, have been obtained for most cases (30 examples).
Von Keutz, Timo,Cantillo, David,Kappe, C. Oliver
supporting information
p. 7537 - 7541
(2020/10/12)

Lipase mediated enzymatic kinetic resolution of phenylethyl halohydrins acetates: A case of study and rationalization
Racemic phenylethyl halohydrins acetates containing several groups attached to the aromatic ring were resolved via hydrolysis reaction in the presence of lipase B from Candida antarctica (Novozym 435). In all cases, the kinetic resolution was highly selective (E > 200) leading to the corresponding (S)-β-halohydrin with ee > 99 %. However, the time required for an ideal 50 % conversion ranged from 15 min for 2,4-dichlorophenyl chlorohydrin acetate to 216 h for 2-chlorophenyl bromohydrin acetate. Six chlorohydrins and five bromohydrins were evaluated, the latter being less reactive. For the β-brominated substrates, steric hindrance on the aromatic ring played a crucial role, which was not observed for the β-chlorinated derivatives. To shed light on the different reaction rates, docking studies were carried out with all the substrates using MD simulations. The computational data obtained for the β-brominated substrates, based on the parameters analysed such as NAC (near attack conformation), distance between Ser-O and carbonyl-C and oxyanion site stabilization were in agreement with the experimental results. On the other hand, the data obtained for β-chlorinated substrates suggested that physical aspects such as high hydrophobicity or induced change in the conformation of the enzymatic active site are more relevant aspects when compared to steric hindrance effects.
Fonseca, Thiago de Sousa,Vega, Kimberly Benedetti,da Silva, Marcos Reinaldo,de Oliveira, Maria da Concei??o Ferreira,de Lemos, Telma Leda Gomes,Contente, Martina Letizia,Molinari, Francesco,Cespugli, Marco,Fortuna, Sara,Gardossi, Lucia,de Mattos, Marcos Carlos
(2020/02/18)

Enantiocomplementary C–H Bond Hydroxylation Combining Photo-Catalysis and Whole-Cell Biocatalysis in a One-Pot Cascade Process
Enantiocomplementary hydroxylation of alkyl aromatics through a one-pot photo-biocatalytic cascade reaction is described. The photoredox process is implemented in aqueous phase with O2 as oxidant and the subsequent (R)- or (S)-selective bioreduction is performed by whole cell system without the addition of the expensive cofactor (NADPH). This mild, operationally simple protocol transforms a wide variety of readily available aromatic compounds into valuable chiral alcohols with high yield (up to 90 %) and stereoselectivity (up to 99 %), thereby displaying important potentials in organic synthesis.
Peng, Yongzhen,Li, Danyang,Fan, Jiajie,Xu, Weihua,Xu, Jian,Yu, Huilei,Lin, Xianfu,Wu, Qi
p. 821 - 825
(2020/02/20)

One-pot synthesis of 4-aryl-2-aminothiazoles from styrenes and thioureas promoted by tribromoisocyanuric acid
A simple and efficient one-pot protocol has been developed for the conversion of styrenes into 4-aryl-2-aminothiazoles using readily available starting materials. Tribromoisocyanuric acid was successfully used for the co-bromination and oxidation of styrenes to give phenacyl bromides, which in the presence of thioureas produced the corresponding 4-aryl-2-aminothiazoles in 48–70% yield. The protocol involves three reactions in one process: a tandem (formation of phenacyl bromides from styrenes) followed by a telescoped (conversion to thiazole) reaction.
de Andrade, Vitor S.C.,de Mattos, Marcio C.S.
supporting information

(2020/07/03)

Visible-light-triggered Catalytic Halohydrin Synthesis from Epoxides and Trichloroacetonitrile by Copper and Iron Salts
Preparation of vicinal halohydrins, in which copper or iron chlorides catalyze the ring-opening reaction of epoxides with visible light effectively, is described. The use of trichloroacetonitrile as a halogen source enables catalytic HCl generation under the mild conditions. This method can also be applied to the aziridine ring-opening reaction.
Toda, Yasunori,Tanaka, Katsumi,Matsuda, Riki,Suga, Hiroyuki
supporting information
p. 1469 - 1471
(2019/12/02)

Enantioselective Reduction of α,β-Unsaturated Ketones and Aryl Ketones by Perakine Reductase
This report describes the enantioselective reduction of structurally diverse α,β-unsaturated ketones and aryl ketones by perakine reductase (PR) from Rauvolfia. This enzymatic reduction produces α-chiral allylic and aryl alcohols with excellent enantioselectivity and most of the products in satisfactory yields. Furthermore, the work demonstrates 1 mmol scale reactions for product delivery without any detrimental effect on yield and enantioselectivity. The catalytic mechanism, determined by 3D-structure-based modeling of PR and ligand complexes, is also described.
Cai, Sheng,Shao, Nana,Chen, Yuanyuan,Li, Anbang,Pan, Jie,Zhu, Huajian,Zou, Hongbin,Zeng, Su,Sun, Lianli,Zhao, Jinhao
supporting information
p. 4411 - 4414
(2019/05/22)

A new entry of highly selective and nucleophilic BrH2C-and CLH2c-titanium complexes for carbonyl coupling
The direct coupling of various aldehydes and ketones with CH2Br2 or CH2Cl2 promoted by TiCl4-Mg bimetallic complex provides an extremely simple, practical, and efficient approach for the construction of bromomethyl or chloromethyl carbinols. The high chemoselectivity of this chemistry is illus-trated by the TiCl4-Mg-promoted selective coupling of CH2Br2 or CH2Cl2 with an aldehyde in the presence of ketone and selective transfer of CH2Br or CH2Cl to saturated carbonyl moiety. This protocol is also suitable for sterically hindered and enoliza-ble carbonyl compounds.
Yan, Tu Hsin,Ananthan, Bakthavachalam,Chang, Su Haur
p. 778 - 787
(2019/01/24)

Laminaria digitata and palmaria palmata seaweeds as natural source of catalysts for the cycloaddition of CO2 to Epoxides
Seaweed powder has been found to act as an effective catalyst for the fixation of CO2 into epoxides to generate cyclic carbonates under solvent free conditions. Model background reactions were performed using metal halides and amino acids typically found in common seaweeds which showed potassium iodide (KI) to be the most active. The efficacy of the seaweed catalysts kelp (Laminaria digitata) and dulse (Palmaria palmata) was probed based on particle size, showing that kelp possessed greater catalytic ability, achieving a maximum conversion and selectivity of 63.7% to styrene carbonate using a kelp loading of 80% by weight with respect to epoxide, 40 bar of CO2, 120?C for 3 h. Maximizing selectivity was difficult due to the generation of diol side product from residual H2O found in kelp, along with a chlorinated by-product thought to form due to a high quantity of chloride salts in the seaweeds. Data showed there was loss of organic matter upon use of the kelp catalyst, likely due to the breakdown of organic compounds and their subsequent removal during product extraction. This was highlighted as the likely cause of loss of catalytic activity upon reuse of the Kelp catalyst.
Comerford, James W.,Gray, Thomas,Lie, Yann,Macquarrie, Duncan J.,North, Michael,Pellis, Alessandro
(2019/01/21)

Efficient hydroboration of carbonyls by an iron(II) amide catalyst
An easily prepared iron(ii) amide precatalyst enables the selective hydroboration of carbonyls with HBpin (pinacolborane) in the absence of any additive. The reactions proceed with low catalytic loading (1-3 mol%) under mild reaction conditions and display wide functional group compatibility. Aldehydes are selectively hydroborated in the presence of other reducible functional groups, such as ketones, alkenes, nitriles, esters, amides, acids and halides.
Baishya, Ashim,Baruah, Swavalina,Geetharani
p. 9231 - 9236
(2018/07/29)

Reaction of Styrene with Chlorine Dioxide
Reaction of styrene with chlorine dioxide under various conditions selectively produces 1-phenyl- 2-chloroethanone, with 1-phenyl-2-chloroethanol, 2-hydroxy-1-phenylethanone, (1,2-dichloroethyl)benzene, (2-chloro-1-phenyl)ethene, and (1,2,2-trichloroethyl
Loginova,Chukicheva, I. Yu.,Kuchin
p. 825 - 828
(2018/06/14)

Efficient conversion of alkenes to chlorohydrins by a Ru-based artificial enzyme
Artificial enzymes are required to catalyse non-natural reactions. Here, a hybrid catalyst was developed by embedding a novel Ru complex in the transport protein NikA. The protein scaffold activates the bound Ru complex to produce a catalyst with high regio- and stereo-selectivity. The hybrid efficiently and stably produced α-hydroxy-β-chloro chlorohydrins from alkenes (up to 180 TON with a TOF of 1050 h?1).
Lopez, Sarah,Rondot, Laurianne,Cavazza, Christine,Iannello, Marina,Boeri-Erba, Elisabetta,Burzlaff, Nicolai,Strinitz, Frank,Jorge-Robin, Adeline,Marchi-Delapierre, Caroline,Ménage, Stéphane
supporting information
p. 3579 - 3582
(2017/03/31)

Halofunctionalization of alkenes by vanadium chloroperoxidase from: Curvularia inaequalis
The vanadium-dependent chloroperoxidase from Curvularia inaequalis is a stable and efficient biocatalyst for the hydroxyhalogenation of a broad range of alkenes into halohydrins. Up to 1 200 000 TON with 69 s-1 TOF were observed for the biocatalyst. A bienzymatic cascade to yield epoxides as reaction products is presented.
Dong, Jia Jia,Fernández-Fueyo, Elena,Li, Jingbo,Guo, Zheng,Renirie, Rokus,Wever, Ron,Hollmann, Frank
supporting information
p. 6207 - 6210
(2017/07/10)

Method for synthesizing N-methylphenethyl ethanolamine and hydrochloride thereof
The invention relates to a method for synthesizing N-methylphenethyl ethanolamine and hydrochloride thereof, and belongs to the technical field of organic synthesis. The method comprises the following steps: dissolving styrene and sodium chloride in a mixed solvent, sequentially adding sulfuric acid aqueous solution and sodium periodate at negative 5-5 DEG C, heating and stirring to react, adding a sodium thiosulfate aqueous solution for a quenching reaction, regulating the pH value to be 8, extracting and concentrating to obtain intermediate (I); adding a methylamine aqueous solution into a reaction bottle, slowly dropwise adding the intermediate (I) into the reaction bottle, stirring overnight at room temperature, performing HPLC detection reaction, and concentrating at reduced pressure to obtain the N-methylphenethyl ethanolamine. In the method for synthesizing N-methylphenethyl ethanolamine, raw materials have low price and are easily available, a low-price conventional reagent is adopted as the reagent, so that the method has low synthesizing cost, mild reaction condition and high conversion rate; and the prepared N-methylphenethyl ethanolamine and hydrochloride thereof have high yield and high purity, and have high quality.
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Paragraph 0039; 0045-0058

(2017/08/30)

Intermolecular Halogenation/Esterification of Alkenes with N-Halosuccinimide and Acetic Acid Catalyzed by 1,4-Diazabicyclo[2.2.2]octane
1,4-Diazabicyclo[2.2.2]octane (DABCO) is a suitable Lewis base that acts as an organocatalyst in the activation of N-chlorosuccinimide (NCS) towards the chlorination of alkenes. The chloriranium ion formed from NCS and the alkene, can be intermolecularly opened by a nucleophile, such as acetic acid, to produce highly functionalized trans-chloro esters in high yields. The protocol is also applied to the synthesis of chlorohydrins and chloro ethers using water or methanol as nucleophiles instead of acetic acid. Brominated analogs can also be synthesized from alkenes and N-bromosuccinimide (NBS) in the presence of various basic catalysts. However, the reaction patterns seem to be remarkably different. The catalytic performance of bases in the bromoesterification of alkenes was found to be strongly affected by their Br?nsted basicity, suggesting that acetyl hypobromite, formed in situ from NBS and acetic acid, acts as a real brominating agent in these systems. (Figure presented.).
Pimenta, Laura S.,Gusevskaya, Elena V.,Alberto, Eduardo E.
supporting information
p. 2297 - 2303
(2017/07/07)

Immobilization of Amano lipase from Pseudomonas fluorescens on silk fibroin spheres: an alternative protocol for the enantioselective synthesis of halohydrins
The search for a new, efficient, cheaper and sustainable matrix for lipase immobilization is a growing area in biotechnology. Amano lipase from Pseudomonas fluorescens was immobilized on silk fibroin spheres and used in the enzymatic kinetic resolution of halohydrins, to obtain optically active epoxides (up to 99% ee), important precursors in the synthesis of derivative antifungal azoles. This paper reinforces the versatility of silk fibroin as a support for heterogeneous catalysts.
Ferreira, Irlon M.,Yoshioka, Sergio A.,Comasseto, Jo?o V.,Porto, André L. M.
p. 12650 - 12658
(2017/03/11)

A carbonyl reductase from: Candida parapsilosis ATCC 7330: Substrate selectivity and enantiospecificity
Candida parapsilosis ATCC 7330, a rich source of highly stereospecific oxidoreductases, catalyzes oxidation-reduction of a plethora of compounds yielding industrially important intermediates. An (S)-specific carbonyl reductase (SRED) purified and characterized from this yeast is reported here. (R)-Specific carbonyl reductase (CpCR) was reported by us earlier. SRED asymmetrically reduces ketones with excellent enantiospecificity (ee > 99%) and α-ketoesters with higher catalytic activity but moderate enantiospecificity (ee 70%) in the presence of NADPH. Minimal activity is shown towards the reduction of aldehydes. While the reduction of α-ketoesters with SRED can occur with either NADPH or NADH, for ketone reduction SRED requires NADPH specifically. SRED with a subunit molecular weight of 30 kDa shows optimal activity at pH 5.0 and 25 °C, and its activity is affected by Cu2+. Taken together, SRED and CpCR offer substrates which on asymmetric reduction give products of opposite absolute configurations.
Sudhakara, Sneha,Chadha, Anju
supporting information
p. 4165 - 4171
(2017/07/10)

Extreme halophilic alcohol dehydrogenase mediated highly efficient syntheses of enantiopure aromatic alcohols
Enzymatic synthesis of enantiopure aromatic secondary alcohols (including substituted, hetero-aromatic and bicyclic structures) was carried out using halophilic alcohol dehydrogenase ADH2 from Haloferax volcanii (HvADH2). This enzyme showed an unprecedented substrate scope and absolute enatioselectivity. The cofactor NADPH was used catalytically and regenerated in situ by the biocatalyst, in the presence of 5% ethanol. The efficiency of HvADH2 for the conversion of aromatic ketones was markedly influenced by the steric and electronic factors as well as the solubility of ketones in the reaction medium. Furthermore, carbonyl stretching band frequencies ν (CO) have been measured for different ketones to understand the effect of electron withdrawing or donating properties of the ketone substituents on the reaction rate catalyzed by HvADH2. Good correlation was observed between ν (CO) of methyl aryl-ketones and the reaction rate catalyzed by HvADH2. The enzyme catalyzed the reductions of ketone substrates on the preparative scale, demonstrating that HvADH2 would be a valuable biocatalyst for the preparation of chiral aromatic alcohols of pharmaceutical interest.
Alsafadi, Diya,Alsalman, Safaa,Paradisi, Francesca
p. 9169 - 9175
(2017/11/15)

Exploiting a beast in carbenoid chemistry: Development of a straightforward direct nucleophilic fluoromethylation strategy
The first direct and straightforward nucleophilic fluoromethylation of organic compounds is reported. The tactic employs a fleeting lithium fluorocarbenoid (LiCH2F) generated from commercially available fluoroiodomethane. Precise reaction conditions were developed for the generation and synthetic exploitation of such a labile species. The versatility of the strategy is showcased in ca. 50 examples involving a plethora of electrophiles. Highly valuable chemicals such as fluoroalcohols, fluoroamines, and fluoromethylated oxygenated heterocycles could be prepared in very good yields through a single synthetic operation. The scalability of the reaction and its application to complex molecular architectures (e.g., steroids) are documented.
Parisi, Giovanna,Colella, Marco,Monticelli, Serena,Romanazzi, Giuseppe,Holzer, Wolfgang,Langer, Thierry,Degennaro, Leonardo,Pace, Vittorio,Luisi, Renzo
supporting information
p. 13648 - 13651
(2017/11/06)

Difunctionalization of Alkenes Using 1-Chloro-1,2-benziodoxol-3-(1H)-one
Difunctionalization of alkenes with 1-chloro-1,2-benziodoxol-3-(1H)-one (1) was investigated. Various additional nucleophiles were tested, and oxychlorination, dichlorination, azidochlorination, chlorothiocyanation, and iodoesterfication were demonstrated. The oxychlorination product was obtained efficiently when the reaction was operated in water. Dichlorination occurred in the presence of a Lewis basic promoter, such as 4-phenylpyridine N-oxide, as an additive. The reaction with in situ-generated azido anion afforded azidochlorinated compounds with a chlorine atom at the terminal position, while the reaction with trimethylsilyl isothiocyanate produced chlorothiocyanation adducts with a chlorine atom at the benzylic position. On the other hand, when 1 was treated with tetra-n-butylammonium iodide prior to the addition of alkenes, only iodoesterification occurred selectively. These mild reactions enable convenient site-selective difunctionalizations of substrates having two alkene moieties. NMR experiments suggested that the electrophilic reactive species in each reaction varied depending on the nature of the added nucleophile.
Egami, Hiromichi,Yoneda, Takahiro,Uku, Minako,Ide, Takafumi,Kawato, Yuji,Hamashima, Yoshitaka
p. 4020 - 4030
(2016/06/09)

External trapping of halomethyllithium enabled by flow microreactors
This work demonstrates that the accurate control of the reaction parameters realized within microreactor systems allowed for a taming of the reactivity of thermally unstable intermediates such as haloalkyllithiums. The first example of effective external trapping of a reactive carbenoid such as the chloromethyllithium is described. By using microreactor systems, a continuous flow synthesis of chloro alcohols and chloro amines could be achieved with high yields. By controlling the residence time the highly reactive chloromethyllithium could be generated and reacted with electrophiles at temperatures much higher than in batch-mode and without internal quenching. The developed continuous-flow process matches the requirements for sustainability.
Degennaro, Leonardo,Fanelli, Flavio,Giovine, Arianna,Luisi, Renzo
supporting information
p. 21 - 27
(2015/01/30)

Asymmetric Reduction of Electron-Rich Ketones with Tethered Ru(II)/TsDPEN Catalysts Using Formic Acid/Triethylamine or Aqueous Sodium Formate
The asymmetric transfer hydrogenation (ATH) of ketones under aqueous conditions using tethered Ru(II)/6-arene/diamine catalysts is described, as is the ATH of electron-rich substrates containing amine and methoxy groups on the aromatic rings. Although such substrates are traditionally challenging ones for ATH, the tethered catalysts work very efficiently. In the case of amino-substituted ketones, aqueous conditions give excellent results; however, for methoxy-substituted substrates, the more established formic acid/triethylamine system gives superior results.
Soni, Rina,Hall, Thomas H.,Mitchell, Benjamin P.,Owen, Matthew R.,Wills, Martin
p. 6784 - 6793
(2015/10/06)

The vicinal functionalization of olefins: A facile route to the direct synthesis of β-chlorohydrins and β-chloroethers
An efficient and environmentally benign protocol for the synthesis of vicinal chlorohydroxy and chloromethoxy derivatives in a highly regioselective manner from olefins using NH4Cl as a chlorine source and oxone as an oxidant in aqueous acetone and methanol is demonstrated. This methodology offers an additive and metal chloride free approach and is endowed with simple reaction conditions, high yields a broad substrate scope and good functional group tolerance. Moreover, the aromatic substrates with a terminal double bond exhibited merely Markovnikov selectivity, while the internal alkenes show exclusive regiocontrol and low to moderate diastereoselectivity.
Swamy, Peraka,Kumar, Macharla Arun,Reddy, Marri Mahender,Naresh, Mameda,Srujana, Kodumuri,Narender, Nama
p. 26288 - 26294
(2014/07/08)

Kinetics and mechanism of styrene epoxidation by chlorite: Role of chlorine dioxide
An investigation of the kinetics and mechanism for epoxidation of styrene and para-substituted styrenes by chlorite at 25 °C in the pH range of 5-6 is described. The proposed mechanism in water and water/acetonitrile includes seven oxidation states of chlorine (-I, 0, I, II, III, IV, and V) to account for the observed kinetics and product distributions. The model provides an unusually detailed quantitative mechanism for the complex reactions that occur in mixtures of chlorine species and organic substrates, particularly when the strong oxidant chlorite is employed. Kinetic control of the reaction is achieved by the addition of chlorine dioxide to the reaction mixture, thereby eliminating a substantial induction period observed when chlorite is used alone. The epoxidation agent is identified as chlorine dioxide, which is continually formed by the reaction of chlorite with hypochlorous acid that results from ClO produced by the epoxidation reaction. The overall stoichiometry is the result of two competing chain reactions in which the reactive intermediate ClO reacts with either chlorine dioxide or chlorite ion to produce hypochlorous acid and chlorate or chloride, respectively. At high chlorite ion concentrations, HOCl is rapidly eliminated by reaction with chlorite, minimizing side reactions between HOCl and Cl2 with the starting material. Epoxide selectivity (>90% under optimal conditions) is accurately predicted by the kinetic model. The model rate constant for direct reaction of styrene with ClO2(aq) to produce epoxide is (1.16 ± 0.07) × 10-2 M -1 s-1 for 60:40 water/acetonitrile with 0.20 M acetate buffer. Rate constants for para substituted styrenes (R = -SO3 -, -OMe, -Me, -Cl, -H, and -NO2) with ClO2 were determined. The results support the radical addition/elimination mechanism originally proposed by Kolar and Lindgren to account for the formation of styrene oxide in the reaction of styrene with chlorine dioxide.
Leigh, Jessica K.,Rajput, Jonathan,Richardson, David E.
supporting information
p. 6715 - 6727
(2014/07/22)

Versatile iridicycle catalysts for highly efficient and chemoselective transfer hydrogenation of carbonyl compounds in water
Cyclometalated iridium complexes are shown to be highly efficient and chemoselective catalysts for the transfer hydrogenation of a wide range of carbonyl groups with formic acid in water. Examples include α-substituted ketones (α-ether, α-halo, α-hydroxy, α-amino, α-nitrile or α-ester), α-keto esters, β-keto esters and α,β-unsaturated aldehydes. The reduction was carried out at substrate/catalyst ratios of up to 50000 at pH 4.5 and required no organic solvent. The protocol provides a practical, easy and efficient way for the synthesis of β-functionalised secondary alcohols, such as β-hydroxyethers, β-hydroxyamines and β-hydroxyhalo compounds, which are valuable intermediates in pharmaceutical, fine chemical, perfume and agrochemical synthesis. Water wonder: Iridicycle catalysts are versatile and allow the highly efficient and chemoselective transfer hydrogenation of a variety of carbonyl compounds, including problematic and challenging ones, with formate in neat water (see scheme).
Talwar, Dinesh,Wu, Xiaofeng,Saidi, Ourida,Salguero, Noemí Poyatos,Xiao, Jianliang
supporting information
p. 12835 - 12842
(2015/03/30)

Steric vs. electronic effects in the Lactobacillus brevis ADH-catalyzed bioreduction of ketones
Lactobacillus brevis ADH (LBADH) is an alcohol dehydrogenase that is commonly employed to reduce alkyl or aryl ketones usually bearing a methyl, an ethyl or a chloromethyl as a small ketone substituent to the corresponding (R)-alcohols. Herein we have tested a series of 24 acetophenone derivatives differing in their size and electronic properties for their reduction employing LBADH. After plotting the relative activity against the measured substrate volumes we observed that apart from the substrate size other effects must be responsible for the activity obtained. Compared to acetophenone (100% relative activity), other small substrates such as propiophenone, α,α, α-trifluoroacetophenone, α-hydroxyacetophenone, and benzoylacetonitrile had relative activities lower than 30%, while medium-sized ketones such as α-bromo-, α,α-dichloro-, and α,α-dibromoacetophenone presented relative activities between 70% and 550%. Moreover, the comparison between the enzymatic activity and the obtained final conversions using an excess or just 2.5 equiv. of the hydrogen donor 2-propanol, denoted again deviations between them. These data supported that these hydrogen transfer (HT) transformations are mainly thermodynamically controlled. For instance, bulky α-halogenated derivatives could be quantitatively reduced by LBADH even employing 2.5 equiv. of 2-propanol independently of their kinetic values. Finally, we found good correlations between the IR absorption band of the carbonyl groups and the degrees of conversion obtained in these HT processes, making this simple method a convenient tool to predict the success of these transformations. The Royal Society of Chemistry.
Rodriguez, Cristina,Borzecka, Wioleta,Sattler, Johann H.,Kroutil, Wolfgang,Lavandera, Ivan,Gotor, Vicente
supporting information
p. 673 - 681
(2014/01/06)

Laccase/TEMPO-mediated system for the thermodynamically disfavored oxidation of 2,2-dihalo-1-phenylethanol derivatives
An efficient methodology to oxidize β,β-dihalogenated secondary alcohols employing oxygen was achieved in a biphasic medium using the laccase from Trametes versicolor/TEMPO pair, providing the corresponding ketones in a clean fashion under very mild conditions. Moreover, a chemoenzymatic protocol has been applied successfully to deracemize 2,2-dichloro-1-phenylethanol combining this oxidation with an alcohol dehydrogenase-catalyzed bioreduction. the Partner Organisations 2014.
Kedziora, Kinga,Diaz-Rodriguez, Alba,Lavandera, Ivan,Gotor-Fernandez, Vicente,Gotor, Vicente
supporting information
p. 2448 - 2453
(2014/05/06)

Efficient synthesis of chlorohydrins using ClCH2MgCl·LiCl
The mixed lithium-magnesium carbenoid ClCH2MgCl·LiCl was easily generated in THF through the reaction of chloroiodomethane with i-PrMgCl·LiCl at -78 °C. This reagent reacts well with a number of aldehydes to give the corresponding chlorohydrins in good yields.
Nishimura, Rodolfo H.V.,Toledo, Fabiano T.,Lopes, Jo?o L.C.,Clososki, Giuliano C.
p. 287 - 290
(2013/02/23)

Chemoselective synthesis of N-substituted α-amino-α′- chloro ketones via chloromethylation of glycine-derived Weinreb amides
Functionalized α-arylamino-α′-chloro ketones are obtained in high yield via a straightforward homologation reaction of Weinreb amides derived from N-arylglycines using in situ generated chloromethyllithium. The use of the Weinreb amides is essential and allows the chemoselective homologation of N-aryl-N-substituted glycine analogues, a transformation which is not possible using similar glycine esters. The procedure is promising for the large-scale preparation of α-amino-α′-chloropropanones, which are valuable precursors for a variety of bioactive compounds. Copyright
Pace, Vittorio,Holzer, Wolfgang,Verniest, Guido,Alcantara, Andres R.,De Kimpe, Norbert
supporting information
p. 919 - 926
(2013/05/08)

Trichloromethyl ketones: Asymmetric transfer hydrogenation and subsequent Jocic-type reactions with amines
Amino-amides are important pharmaceutical building-blocks. The enantioselective reduction of trichloromethyl ketones using ruthenium transfer hydrogenation catalysts is reported. The products react in a range of Jocic-type reactions to give enantiomerically enriched amino-amides.
Perryman, Michael S.,Harris, Matthew E.,Foster, Jade L.,Joshi, Anushka,Clarkson, Guy J.,Fox, David J.
supporting information
p. 10022 - 10024
(2013/10/22)

Aromatic substitution in ball mills: Formation of aryl chlorides and bromides using potassium peroxomonosulfate and NaX
Aryl chlorides and bromides are formed from arenes in a ball mill using KHSO5 and NaX (X = Cl, Br) as oxidant and halogen source, respectively. Investigation of the reaction parameters identified operating frequency, milling time, and the number of milling balls as the main influencing variables, as these determine the amount of energy provided to the reaction system. Assessment of liquid-assisted grinding conditions revealed, that the addition of solvents has no advantageous effect in this special case. Preferably activated arenes are halogenated, whereby bromination afforded higher product yields than chlorination. Most often reactions are regio- and chemoselective, since p-substitution was preferred and concurring side-chain oxidation of alkylated arenes by KHSO5 was not observed. The Royal Society of Chemistry.
Schmidt, Robert,Stolle, Achim,Ondruschka, Bernd
p. 1673 - 1679
(2013/02/22)

Decarboxylative bromination of cinnamic acids by 2-iodoxybenzoic acid with tetrabutylammonium bromide
The decarboxylative bromination of cinnamic acids using the hypervalent iodine reagent 2-iodoxybenzoic acid with tetrabutylammonium bromide is described, providing good to excellent yields of bromostyrenes. Bromostyrenes are useful coupling components in a wide range of transition metal-catalysed coupling reactions.
Han, Jianlei,Wei, Yuping
p. 247 - 248
(2012/09/22)

RUTHENIUM-DIAMINE COMPLEXES AND METHOD FOR PRODUCING OPTICALLY ACTIVE COMPOUNDS
Provided is a catalyst for asymmetric reduction, which can be produced by a convenient and safe production method, has a strong catalytic activity, and has excellent stereoselectivity. The present invention relates to a ruthenium complex represented by the following formula (1): wherein R1 represents an alkyl group or the like; Y represents a hydrogen atom; X represents a halogen atom or the like; j and k each represent 0 or 1; R2 and R3 each represent an alkyl group or the like; R11 to R19 each represent a hydrogen atom, an alkyl group or the like; Z represents oxygen or sulfur; n1 represents 1 or 2; and n2 represents an integer from 1 to 3, a method for producing the ruthenium complex, a catalyst for asymmetric reduction formed from the ruthenium complex, and methods for selectively producing an optically active alcohol and an optically active amine using the catalyst for asymmetric reduction.
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Page/Page column 23; 25

(2012/03/26)

Immobilization of marine fungi on silica gel, silica xerogel and chitosan for biocatalytic reduction of ketones
The scanning electron microscopy (SEM) analysis showed that whole living hyphal of marine fungi Aspergillus sclerotiorum CBMAI 849 and Penicillium citrinum CBMAI 1186 were immobilized on support matrices of silica gel, silica xerogel and/or chitosan. P. citrinum immobilized on chitosan catalyzed the quantitative reduction of 1-(4-methoxyphenyl)-ethanone (1) to the enantiomer (S)-1-(4-methoxyphenyl)-ethanol (3b), with excellent enantioselectivity (ee > 99%, yield = 95%). Interestingly, ketone 1 was reduced with moderate selectivity and conversion to alcohol 3b (ee = 69%, c 40%) by the free mycelium of P. citrinum. This free mycelium of P. citrinum catalyzed the production of the (R)-alcohol 3a, the antipode of the alcohol produced by the immobilized cells. P. citrinum immobilized on chitosan also catalyzed the bioreduction of 2-chloro-1-phenylethanone (2) to 2-chloro-1-phenylethanol (4a,b), but in this case without optical selectivity. These results showed that biocatalytic reduction of ketones by immobilization hyphal of marine fungi depends on the xenobiotic substrate and the support matrix used.
Rocha, Lenilson Coutinho,De Souza, Adriano Lopes,Rodrigues Filho, Ubirajara Pereira,Campana Filho, Sergio Paulo,Sette, Lara Duraes,Porto, Andre Luiz Meleiro
p. 160 - 165
(2012/11/06)

Electrochemically induced titanocene-mediated reductive opening of epoxides
A new method for chemo- and regioselective electrochemical reductive opening of epoxides yielding primary alcohols with titanocene dichloride as a catalyst has been elaborated.
Nikitin, Oleg M.,Magdesieva, Tatiana V.
scheme or table
p. 194 - 195
(2011/11/12)

Highly regio- and diastereoselective halohydroxylation of olefins: A facile synthesis of vicinal halohydrins
An efficient method for the synthesis of vicinal chlorohydrin or bromohydrin derivatives has been developed on the basis of direct halohydroxylation of various olefins with electrondonating or withdrawing substituent. The reactions were carried out under mild conditions in the presence of N-tosyl-l-threonine (NTsLT) as an acidic additive using chloramine T trihydrate, 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) or N-bromoacetamide (AcNHBr) as the halogen source, respectively, affording the corresponding vicinal halohydrins in good to high yields with excellent regio- and stereoselectivities.
Zhang, Jinglei,Wang, Jie,Qiu, Zhuibai,Wang, Yang
experimental part
p. 6859 - 6867
(2011/10/02)

MPV reduction using AlIII-calix[4]arene Lewis acid catalysts: Molecular-level insight into effect of ketone binding
Catalytic Meerwein-Ponndorf-Verley (MPV) reduction using Al III-calix[4]arene complexes is investigated as a model system that requires the bringing together of two different chemical species, ketone and alkoxide, within a six-membered transition state. Two-point versus one-point ketone binding is demonstrated to be the most salient feature that controls MPV catalysis rate. A 7.7-fold increase in rate is observed when comparing reactants consisting of a bidentate Cl-containing ketone and sterically and electronically similar but looser-binding ketones, which are substituted with H and F. The one-point and two-point nature of ketone binding for the various ketones investigated is independently assessed using a combination of structural data derived from single-crystal X-ray diffraction and DFT-based molecular modeling. Using MPV catalysis with inherently chiral calix[4]arenes, the effect of multiple point reactant binding on enantioselectivity is elucidated. A higher denticity of ketone binding appears to increase the sensitivity of the interplay between chiral active site structure and MPV reduction enantioselectivity.
Nandi, Partha,Matvieiev, Yuriy I.,Boyko, Vyacheslav I.,Durkin, Kathleen A.,Kalchenko, Vitaly I.,Katz, Alexander
experimental part
p. 42 - 49
(2011/12/13)

Purification and characterization of an NADH-dependent alcohol dehydrogenase from Candida maris for the synthesis of optically active 1-(pyridyl)ethanol derivatives
A novel (R)-specific alcohol dehydrogenase (AFPDH) produced by Candida maris IFO10003 was purified to homogeneity by ammonium sulfate fractionation, DEAE-Toyopearl, and Phenyl-Toyopearl, and characterized. The relative molecular mass of the native enzyme was found to be 59,900 by gel filtration, and that of the subunit was estimated to be 28,900 on SDS-polyacrylamide gel electrophoresis. These results suggest that the enzyme is a homodimer. It required NADH as a cofactor and reduced various kinds of carbonyl compounds, including ketones and aldehydes. AFPDH reduced acetylpyridine derivatives, β-keto esters, and some ketone compounds with high enantioselectivity. This is the first report of an NADH-dependent, highly enantioselective (R)-specific alcohol dehydrogenase isolated from a yeast. AFPDH is a very useful enzyme for the preparation of various kinds of chiral alcohols.
Kawano, Shigeru,Yano, Miho,Hasegawa, Junzo,Yasohara, Yoshihiko
experimental part
p. 1055 - 1060
(2012/02/03)

Ketone-alcohol hydrogen-transfer equilibria: Is the biooxidation of halohydrins blocked?
To ensure the quasi-irreversibility of the oxidation of alcohols coupled with the reduction of ketones in a hydrogen-transfer (HT) fashion, stoichiometric amounts of a-halo carbonyl compounds have been employed as hydrogen acceptors. The reason that these substrates lead to quasi-quantitative conversions has been tacitly attributed to both thermodynamic and kinetic effects. To provide a clear rationale for this behavior, we investigate herein the redox equilibrium of a selected series of ketones and 2-propanol by undertaking a study that combines experimental and theoretical approaches. First, the activity of the (R)-specific alcohol dehydrogenase from Lactobacillus brevis (LBADH) with these substrates was studied. The docking of acetophenone/(R)-l-phenyethanol and a-chloroacetophenone/(S)-2-chloro- lphenylethanol in the active site of the enzyme confirms that there seems to be no structural reason for the lack of reactivity of halohydrins. This assumption is confirmed by the fact that the corresponding aluminum-catalyzed Meerwein-Ponndorf-Verley-Oppenauer (MPVO) reactions afford similar conversions to those obtained with LBADH, showing that the observed reactivity is independent of the catalyst employed. While the initial rates of the enzymatic reductions and the IR v(C=0) values contradict the general belief that electron-withdrawing groups increase the electrophilicity of the carbonyl group, the calculated βG values of the isodesmic redox transformations of these series of ketones/alcohols with 2-propanol/acetone support the thermodynamic control of the reaction. As a result, a general method to predict the degree of conversion obtained in the HT-reduction process of a given ketone based on the IR absorption band of the carbonyl group is proposed, and a strategy to achieve the HT oxidation of halohydrins is also shown.
Bisogno, Fabricio R.,Garcia-Urdiales, Eduardo,Valdes, Haydee,Lavandera, Ivan,Kroutil, Wolfgang,Suarez, Dimas,Gotor, Vicente
body text
p. 11012 - 11019
(2010/11/18)

Simultaneous iridium catalysed oxidation and enzymatic reduction employing orthogonal reagents
An iridium catalysed oxidation was coupled concurrently to an asymmetric biocatalytic reduction in one-pot; thus it was shown for the first time that iridium- and alcohol dehydrogenase-catalysed redox reactions are compatible. As a model system racemic chlorohydrins were transformed to enantioenriched chlorohydrins via an oxidation-asymmetric reduction sequence.
Mutti, Francesco G.,Orthaber, Andreas,Schrittwieser, Joerg H.,Vries, Johannes G. De,Pietschnig, Rudolf,Kroutil, Wolfgang
supporting information; experimental part
p. 8046 - 8048
(2011/01/03)

Candida tropicalis CE017: A new Brazilian enzymatic source for the bioreduction of aromatic prochiral ketones
The reactivity and stereoselectivity showed by a new strain of Candida tropicalis in the reduction of prochiral ketones have been compared with the ones previously attained in our laboratory using microorganisms from the Brazilian biodiversity. In this manner, Candida tropicalis has demonstrated its versatility as stereoselective agent in the bioreduction of a series of aromatic ketones. These prochiral compounds were converted into their corresponding optically alcohols with moderate to excellent stereopreference depending on the substrate structure. Among ketones tested, nitroacetophenones were enzymatically reduced to enantiopure (S)-alcohol with complete conversion.
Vieira, Gizelle A. B.,De Freitas Araujo, Daniel M.,Lemos, Telma L. G.,De Mattos, Marcos Carlos,Da Conceic?a?o F. De Oliveira, Maria,Melo, Va?nia M. M.,De Gonzalo, Gonzalo,Gotor-Ferna?ndez, Vicente,Gotor, Vicente
experimental part
p. 1509 - 1516
(2010/11/04)

Ruthenium-catalysed hydrogenation of aromatic ketones using monodentate phosphoramidite ligands
A ruthenium pre-catalyst containing two equivalents of the bulky monodentate phosphoramidite 3,3′-dimethyl-PipPhos and one equivalent of a chiral diamine such as 1,2-diphenylethylenediamine or 1,2-diaminocyclohexane was used for the asymmetric hydrogenation of aromatic ketones. A range of substituted and unsubstituted aryl alkyl ketones was hydrogenated using only 0.1 mol% of this catalyst with full conversions and enantioselectivities up to 97%. The phosphoramidite and diamine ligands matched when both had the same configuration, i.e., S-phosphoramidite with S,S-diamine. In that case the product was obtained with high enantioselectivity and the R-configuration. The mismatched case produced the product in lower ee. The product configuration was determined by the configuration of the diamine ligand. A mechanistic proposal was made.
Stegink, Bart,Van Boxtel, Lonneke,Lefort, Laurent,Minnaard, Adriaan J.,Feringa, Ben L.,De Vries, Johannes G.
supporting information; experimental part
p. 2621 - 2628
(2010/12/25)

Fast racemisation of chiral amines and alcohols by using cationic half-sandwich ruthena- and iridacycle catalysts
The lipase-catalysed resolution of alcohols and amines yields only 50% of the desired enantiopure product. However, addition of a racemisation catalyst leads to 100% yield in what is called a dynamic kinetic resolution (DKR). There is a need for new racemisation catalysts that are fast and compatible with the conditions of the enzymatic reaction. We show that cationic half-sandwich ruthena- and iridacycle complexes are highly active and efficient in the racemisation of chiral alcohols and amines. Upon activation with base, these complexes are able to selectively racemise alcohols, whereas the non-activated complexes are selective catalysts for the racemisation of amines. We have applied the iridacycles in the DKR of racemic β-chloroalcohols to produce chiral epoxides in a biphasic system in good yields and high ee (ee = enantiomeric excess).
Jerphagnon, Thomas,Gayet, Arnaud J.A.,Berthiol, Florian,Ritleng, Vincent,Mrsic, Natasa,Meetsma, Auke,Pfeffer, Michel,Minnaard, Adriaan J.,Feringa, Ben L.,De Vries, Johannes G.
scheme or table
p. 12780 - 12790
(2010/06/16)

Biocatalytic cascade for the synthesis of enantiopure β-azidoalcohols and β-hydroxynitriles
A three-step, two-enzyme, one-pot reaction sequence starting from prochiral a-chloroketones leading to enantiopure (3- azidoalcohols and (3-hydroxynitriles is described. Asymmetric bioreduction of a-chloroketones by hydrogen transfer catalysed by an alcohol dehydrogenase (ADH) established the stereogenic centre in the first step to furnish enantiopure chlorohydrin intermediates. Subsequent biocatalysed ring closure to the epoxide and nucleophilic ring opening with azide, N3-, or cyanide, CN-, both catalysed by a nonselective halohydrin dehalogenase (Hhe) proceeded with full retention of configuration to give enantiopure (-azidoalcohols and (3-hydroxynitriles, respectively. Both enantiomers of various optically pure (-azidoalcohols and (-hydroxynitriles were synthesised.
Schrittwieser, Joerg H.,Lavandera, Ivan,Seisser, Birgit,Mautner, Barbara,Kroutil, Wolfgang
experimental part
p. 2293 - 2298
(2009/08/17)

Lentinus strigellus: a new versatile stereoselective biocatalyst for the bioreduction of prochiral ketones
Growing cells of the basiodiomycete Lentinus strigellus in potato-dextrose broth have been used for the first time as a biocatalyst in the stereoselective reduction of aromatic and aliphatic ketones. Most of the aromatic ketones were converted into the corresponding optically active alcohols in up to >99% enantiomeric excess under very mild reaction conditions. Among the aliphatic ketones tested, 2-octanone was enzymatically reduced by this microorganism to enantiopure (S)-2-octanol with almost complete conversion.
Barros-Filho, Bartholomeu A.,de Oliveira, Maria da Conceicao F.,Lemos, Telma L.G.,de Mattos, Marcos C.,Gonzalo, Gonzalo de,Gotor-Fernandez, Vicente,Gotor, Vicente
experimental part
p. 1057 - 1061
(2009/10/02)

Empirical method for predicting enantioselectivity in catalytic reactions: demonstration with lipase and oxazaborolidine
We derived a novel equation capable of predicting the degree of enantioselectivity in a catalytic reaction without any knowledge of the reaction mechanism and/or the transition-state structure, and tested the validity of this equation by changing substrates systematically in the lipase or oxazaborolidine-catalyzed reactions. A good correlation was observed between the predicted and observed E values, and the stereochemistry of the products could be predicted correctly in most cases (28 out of 30).
Ema, Tadashi,Ura, Norichika,Yoshii, Masataka,Korenaga, Toshinobu,Sakai, Takashi
experimental part
p. 9583 - 9591
(2010/01/06)