- Engineering the selectivity of aliphatic C-H bond oxidation catalysed by cytochrome P450cam
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The regioselectivity of the catalytic hydroxylation of phenylcyclohexane 1 by cytochrome P450cam can be altered dramatically by site-directed mutagenesis: the Y96F single site mutant gives 81% cis-3-phenylcyclohexanol 2, with 22% enantiomeric excess (ee), while the Y96F-V247A double mutant gives 97% 2 with 42% ee and the Y96F-V247L double mutant gives 83% trans-4-phenylcyclohexanol 4.
- Jones, Nia E.,England, Paul A.,Rouch, Duncan A.,Wong, Luet-Lok
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Read Online
- Direct Asymmetric Hydrogenation and Dynamic Kinetic Resolution of Aryl Ketones Catalyzed by an Iridium-NHC Exhibiting High Enantio- and Diastereoselectivity
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A chiral iridium carbene-oxazoline catalyst is reported that is able to directly and efficiently hydrogenate a wide variety of ketones in excellent yields and good enantioselectivity (up to 93 % ee). Moreover, when using racemic α-substituted ketones, excellent diastereoselectivities were obtained (dr 99:1) by dynamic kinetic resolution of the in situ formed enolate. Overall, the herein described hydrogenation occurs under ambient conditions using low hydrogen pressures, providing a direct and atom efficient method towards chiral secondary alcohols.
- Ayya Swamy P, Chinna,Varenikov, Andrii,de Ruiter, Graham
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supporting information
p. 2333 - 2337
(2020/02/11)
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- Acylative Kinetic Resolution of Alcohols Using a Recyclable Polymer-Supported Isothiourea Catalyst in Batch and Flow
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A polystyrene-supported isothiourea catalyst, based on the homogeneous catalyst HyperBTM, has been prepared and used for the acylative kinetic resolution of secondary alcohols. A wide range of alcohols, including benzylic, allylic, and propargylic alcohols, cycloalkanol derivatives, and a 1,2-diol, has been resolved using either propionic or isobutyric anhydride with good to excellent selectivity factors obtained (28 examples, s values up to 600). The catalyst can be recovered and reused by a simple filtration and washing sequence, with no special precautions needed. The recyclability of the catalyst was demonstrated (15 cycles) with no significant loss in either activity or selectivity. The recyclable catalyst was also used for the sequential resolution of 10 different alcohols using different anhydrides with no cross-contamination between cycles. Finally, successful application in a continuous flow process demonstrated the first example of an immobilized Lewis base catalyst used for the kinetic resolution of alcohols in flow.
- Neyyappadath, Rifahath Mon,Chisholm, Ross,Greenhalgh, Mark D.,Rodríguez-Escrich, Carles,Pericàs, Miquel A.,H?hner, Georg,Smith, Andrew D.
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p. 1067 - 1075
(2018/02/14)
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- (Poly)cationic λ3-Iodane-Mediated Oxidative Ring Expansion of Secondary Alcohols
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Herein, a simplified approach to the synthesis of medium-ring ethers through the electrophilic activation of secondary alcohols with (poly)cationic λ3-iodanes (N-HVIs) is reported. Excellent levels of selectivity are achieved for C–O bond migration over established α-elimination pathways, enabled by the unique reactivity of a novel 2-OMe-pyridine-ligated N-HVI. The resulting hexafluoroisopropanol (HFIP) acetals are readily derivatized with a range of nucleophiles, providing a versatile functional handle for subsequent manipulations. The utility of this methodology for late-stage natural product derivatization was also demonstrated, providing a new tool for diversity-oriented synthesis and complexity-to-diversity (CTD) efforts. Preliminary mechanistic investigations reveal a strong effect of alcohol conformation on the reactive pathway, thus providing a predictive power in the application of this approach to complex molecule synthesis.
- Walters, Jennifer C.,Tierno, Anthony F.,Dubin, Aimee H.,Wengryniuk, Sarah E.
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supporting information
p. 1460 - 1464
(2018/04/06)
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- Diastereoselective and enantioselective alkaline-hydrolysis of 2-aryl-1-cyclohexyl acetate: a CAL-B catalyzed deacylation/acylation tandem process
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Candida antarctica lipase proved to be a particularly efficient lipase for the resolution of racemic 2-arylcyclohexyl acetate in hydrolysis reaction with Na2CO3 in an organic medium. The (1R,2S)-trans-2-arylcyclohexanols 2a–2d were obtained with high ee values (up to >99%) and the selectivity reached E > 200. The influence of the enol ester and the solvent on (±)-trans-2-arylcyclohexanol in the CAL-B catalyzed acylation was also studied and compared with the deacylation. The CAL-B exhibits a better affinity for the alkaline hydrolysis reaction compared with acylation with the enol esters in the same organic solvents. The best conditions were applied to resolve a stereoisomeric mixture cis/trans-2-phenyl-1-cyclohexanol and its corresponding acetate by acylation and deacylation. The obtained results show a highly enantio- and diastereoselectivity of the CAL-B during the acylation and the deacylation in favor of the trans-(R)-enantiomer product. The resolution of a mixture of cis/trans-2-arylcyclohexanols was an easy, convenient approach to provide only one stereoisomer of a mixture of four with high enantiomeric excess.
- Belkacemi, Fatma Zahra,Merabet-Khelassi, Mounia,Aribi-Zouioueche, Louisa,Riant, Olivier
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supporting information
p. 1644 - 1650
(2017/10/12)
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- Directed β C-H Amination of Alcohols via Radical Relay Chaperones
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A radical-mediated strategy for β C-H amination of alcohols has been developed. This approach employs a radical relay chaperone, which serves as a traceless director that facilitates selective C-H functionalization via 1,5-hydrogen atom transfer (HAT) and enables net incorporation of ammonia at the β carbon of alcohols. The chaperones presented herein enable direct access to imidate radicals, allowing their first use for H atom abstraction. A streamlined protocol enables rapid conversion of alcohols to their β-amino analogs (via in situ conversion of alcohols to imidates, directed C-H amination, and hydrolysis to NH2). Mechanistic experiments indicate HAT is rate-limiting, whereas intramolecular amination is product- and stereo-determining.
- Wappes, Ethan A.,Nakafuku, Kohki M.,Nagib, David A.
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supporting information
p. 10204 - 10207
(2017/08/10)
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- Accessing non-natural reactivity by irradiating nicotinamide-dependent enzymes with light
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Enzymes are ideal for use in asymmetric catalysis by the chemical industry, because their chemical compositions can be tailored to a specific substrate and selectivity pattern while providing efficiencies and selectivities that surpass those of classical synthetic methods. However, enzymes are limited to reactions that are found in nature and, as such, facilitate fewer types of transformation than do other forms of catalysis. Thus, a longstanding challenge in the field of biologically mediated catalysis has been to develop enzymes with new catalytic functions. Here we describe a method for achieving catalytic promiscuity that uses the photoexcited state of nicotinamide co-factors (molecules that assist enzyme-mediated catalysis). Under irradiation with visible light, the nicotinamide-dependent enzyme known as ketoreductase can be transformed from a carbonyl reductase into an initiator of radical species and a chiral source of hydrogen atoms. We demonstrate this new reactivity through a highly enantioselective radical dehalogenation of lactones - a challenging transformation for small-molecule catalysts. Mechanistic experiments support the theory that a radical species acts as an intermediate in this reaction, with NADH and NADPH (the reduced forms of nicotinamide adenine nucleotide and nicotinamide adenine dinucleotide phosphate, respectively) serving as both a photoreductant and the source of hydrogen atoms. To our knowledge, this method represents the first example of photo-induced enzyme promiscuity, and highlights the potential for accessing new reactivity from existing enzymes simply by using the excited states of common biological co-factors. This represents a departure from existing light-driven biocatalytic techniques, which are typically explored in the context of co-factor regeneration.
- Emmanuel, Megan A.,Greenberg, Norman R.,Oblinsky, Daniel G.,Hyster, Todd K.
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p. 414 - 417
(2017/04/01)
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- Diastereoselective and Enantioselective Silylation of 2-Arylcyclohexanols
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The silylation-based kinetic resolution of trans 2-arylcyclohexanols was accomplished by employing a triaryl silyl chloride as the derivatizing reagent with a commercially available isothiourea catalyst. The methodology is selective for the trans diastereomer over the cis, which provides an opportunity to selectively derivatize one stereoisomer out of a mixture of four. By employing this technology, a facile, convenient method to form a highly enantiomerically enriched silylated alcohol was accomplished through a one-pot reduction-silylation sequence that started with a 2-aryl-substituted ketone.
- Wang, Li,Akhani, Ravish K.,Wiskur, Sheryl L.
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supporting information
p. 2408 - 2411
(2015/05/27)
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- METHOD FOR PREPARING CHIRAL ALCOHOLS FROM RACEMIC OR MESO ALCOHOLS
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Disclosed is a method for producing a chiral alcohol compound. According to the present invention, a stereoselective reaction between a racemic alcohol compound or a mesoalcohol compound and a silylation agent can be performed in the presence of a chiral catalyst compound to produce a chiral alcohol compound. In this case, a compound obtained by derivatizing oligo ethylene glycol including a hydroxy functional group of a binol derivative, which is an acid portion, and an oligo ethylene glycol functional group, which is an alkali portion, can be used as the chrial catalyst compound.COPYRIGHT KIPO 2016
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Paragraph 0216-0217
(2016/10/10)
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- METHOD FOR PREPARING CHIRAL ALCOHOLS FROM RACEMIC OR MESO ALCOHOLS
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A method for manufacturing a chiral alcohol compound is disclosed. A racemic alcohol compound or a meso alcohol compound and a silylation agent in the presence of a chiral catalyst compound can be reacted in a stereoselective manner to manufacture the chiral alcohol compound. In this case, a compound derivatized with an oligoethylene glycol including an oligoethylene glycol functional group as a base part and a hydroxy functional group of a binol derivative as an acid part can be used as the chiral catalyst compound.COPYRIGHT KIPO 2016
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Paragraph 0216; 0217; 0218; 0439
(2016/10/10)
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- Nickel-catalyzed regiodivergent opening of epoxides with aryl halides: Co-catalysis controls regioselectivity
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Epoxides are versatile intermediates in organic synthesis, but have rarely been employed in cross-coupling reactions. We report that bipyridine-ligated nickel can mediate the addition of functionalized aryl halides, a vinyl halide, and a vinyl triflate to epoxides under reducing conditions. For terminal epoxides, the regioselectivity of the reaction depends upon the cocatalyst employed. Iodide cocatalysis results in opening at the less hindered position via an iodohydrin intermediate. Titanocene cocatalysis results in opening at the more hindered position, presumably via TiIII-mediated radical generation. 1,2-Disubstituted epoxides are opened under both conditions to form predominantly the trans product.
- Zhao, Yang,Weix, Daniel J.
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supporting information
p. 48 - 51
(2014/01/23)
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- Kinetic resolution of secondary alcohols catalyzed by chiral phosphoric acids
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Acid instead of base: Kinetic resolution of secondary alcohols is realized using chiral Bronsted acid catalyzed acylation instead of the conventional basic conditions. A broad range of functional groups are tolerated, such as aldehydes, carboxylic acids, and enoates. The selectivity factor (s) reaches up to 215 at ambient temperature. Copyright
- Harada, Shingo,Kuwano, Satoru,Yamaoka, Yousuke,Yamada, Ken-Ichi,Takasu, Kiyosei
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supporting information
p. 10227 - 10230
(2013/10/21)
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- Influence of chiral thiols on the diastereoselective synthesis of γ-lactams from cyclic anhydrides
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The synthesis of γ-lactams from both four-component and imine-anhydride reactions is reported. The synthesis of 2-phenylcyclohexanethiol is described and this compound was evaluated along with an additional seven chiral thiols. A range of selectivity and yields was observed and comparisons to established reactions are made in order to account for the observed reactivity.
- Younai, Ashkaan,Fettinger, James C.,Shaw, Jared T.
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scheme or table
p. 4320 - 4327
(2012/07/28)
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- Homobenzotetramisole: An effective catalyst for kinetic resolution of aryl-cycloalkanols
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Homobenzotetramisole (HBTM), a ring-expanded analogue of the previously reported catalyst BTM, displays higher catalytic activity and a different structure-selectivity profile. It displays good enantioselectivities in kinetic resolution of secondary benzylic alcohols but is particularly effective for 2-aryl-substituted cycloalkanols.
- Birman, Vladimir B.,Li, Ximin
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supporting information; experimental part
p. 1115 - 1118
(2009/04/07)
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- Enantioselective synthesis of cis-α-substituted cycloalkanols and trans-cycloalkyl amines thereof
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The diastereo- and enantioselective syntheses of trans-cycloalkyl amines was accomplished through a three-step sequence consisting of: (1) asymmetric transfer hydrogenation through dynamic kinetic resolution of bicyclic and monocyclic α-substituted ketones using HCO2H/Et3N as the hydrogen source and TsDPEN-based Ru(II) catalysts, (2) nucleophilic hydroxyl to azide substitution of the resulting cis-cycloalkanols using diphenyl phosphoryl azide under modified Mitsunobu conditions, and (3) reduction of the trans-azide intermediates with LiAlH4 of PPh3/H2O to the desired targets.
- Fernández, Rosario,Ros, Abel,Magriz, Antonio,Dietrich, Hansj?rg,Lassaletta, José M.
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p. 6755 - 6763
(2008/02/11)
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- Reduction of carbonyl compounds by lanthanide metal/2-propanol: In-situ generation of samarium isopropyloxide for stereoselective Meerwein-Ponndorf- Verley reduction
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The reduction of ketones and aldehydes with lanthanide metals (La, Ce, Sm, Yb) and a catalytic amount of iodine (5 mol %) in iPrOH proceeded smoothly to produce the corresponding alcohols as the major products in good yield, while in THF, methanol, and ethanol the pinacols were mainly produced. The yields of alcohols were improved most effectively by the use of Sm metal, the amount of pinacol produced thus being minimized. The actual reducing agent may be samarium isopropyloxide, which mediates the Meerwein-Ponndorf-Verley-type hydride-transfer reaction, since the reaction can be carried out catalytically with respect to samarium. The stereoselectivities of the reductions of the 2- and 4-substituted cyclohexanones with Sm/iPrOH were higher than those achieved with SmI2/iPrOH or Sm/ H20. The asymmetric reduction of acetophenone could be achieved to give the 1-phenylethanol in up to 95% ee in the presence of the chiral ligand 7. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
- Fukuzawa, Shin-Ichi,Nakano, Narihito,Saitoh, Takahide
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p. 2863 - 2867
(2007/10/03)
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- Effective nonenzymatic kinetic resolution of (±)-trans-2-arylcyclohexanols using 3β-acetoxyetienic acid, DCC, and DMAP
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(1R,2S)-trans-2-Arylcyclohexanols of high enantiomerically purity were obtained by the simple stirring of the corresponding (±)-arylcyclohexanols with 3β-acetoxyetienic acid, DCC, and DMAP at room temperature.
- Matsugi, Masato,Hagimoto, Yuri,Nojima, Masatomo,Kita, Yasuyuki
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p. 583 - 584
(2013/09/05)
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- The design of novel N-4′-pyridinyl-α-methyl proline derivatives as potent catalysts for the kinetic resolution of alcohols
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A novel family of chiral acylation catalysts based on a N-4′-pyridinyl-α-methyl proline structure has been studied. A set of 31 compounds has been easily prepared and screened in the kinetic resolution of racemic alcohol 33 resulting in high enantioselectivities in most cases. From results obtained, H-bonding interactions between the catalyst and the substrate would appear essential to afford high enantioselectivity during the catalytic acylation. Additional solvent dependence and anhydride studies have been made to better identify the mechanism. This work has been further extended to the study of a number of structurally different alcohols. Ethanolamine derivatives in particular were found to be highly effective substrates (up to S = 18.8) in the kinetic resolution.
- Priem, Ghislaine,Pelotier, Béatrice,Macdonald, Simon J. F.,Anson, Mike S.,Campbell, Ian B.
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p. 3844 - 3848
(2007/10/03)
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- Recyclable Polyurea-Microencapsulated Pd(0) Nanoparticles: An Efficient Catalyst for Hydrogenolysis of Epoxides
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(Matrix presented) Pd nanoparticles (~2 nm in size) microencapsulated in polyurea is an efficient and recyclable catalyst for reductive ring-opening hydrogenolysis of epoxides, using either HCOOH/Et3N or H2 as a hydrogen donor.
- Ley, Steven V.,Mitchell, Claire,Pears, David,Ramarao, Chandrashekar,Yu, Jin-Quan,Zhou, Wuzong
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p. 4665 - 4668
(2007/10/03)
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- Diastereoselective reduction of alkenylboronic esters as a new method for controlling the stereochemistry of up to three adjacent centers in cyclic and acyclic molecules
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(figure presented) cis-Boronates are readily available via a diastereoselective Pd-catalyzed reduction of tetrasubstituted alkenylboronic esters using H2. Applying the reaction conditions presented to unsaturated open-chain boronic esters allows the stereochemistry of up to three adjacent centers to be controlled.
- Hupe, Eike,Marek, Ilan,Knochel, Paul
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p. 2861 - 2863
(2007/10/03)
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- Free-radical hydroxylation reactions of alkylboronates
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The radical hydroxylation of B-alkylcatecholboranes, easily prepared by hydroboration of olefins, has been investigated. When molecular oxygen was used as oxidizing agent, the corresponding alcohols were obtained directly without alkaline treatment. The presence of Lewis base additives such as Et3N or DABCO has a benefic effect on the selectivity and yield. Alternatively, 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) reacts cleanly with B-alkylcatecholboranes to afford alkyl radicals that can be trapped by a second equivalent of TEMPO to give alkoxyamines. Reduction of the alkoxyamines with zinc in acetic acid affords the desired alcohols. The whole procedure is particularly mild and does not require any basic condition. The two approaches presented in this paper are valuable and represent mild alternatives to the classical alkaline oxidation of organoboranes to alcohols.
- Cadot, Christine,Dalko, Peter I.,Cossy, Janine,Ollivier, Cyril,Chuard, Rachel,Renaud, Philippe
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p. 7193 - 7202
(2007/10/03)
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- Asymmetric synthesis of CDP840 by Jacobsen epoxidation. An unusual syn selective reduction of an epoxide
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An asymmetric synthesis of the PDE IV inhibitor, CDP840 (3) is reported. The absolute stereochemistry was controlled by a Jacobsen epoxidation of the Z triaryl olefin 8 (89% ee) or the E triaryl olefin 9 (48% ee). The disparate results in stereocontrol were interpreted in terms of the 'skewed side-on approach model' proposed by Jacobsen. LiBH4 · BH3 reduction of the epoxides was found to proceed with retention of configuration.
- Lynch,Choi,Churchill,Volante,Reamer,Ball
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p. 9223 - 9228
(2007/10/03)
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- Diastereoselective reduction of cyclohexanones with diisobutylaluminium phenoxides in terms of the isoinversion principle
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The diastereoselectivity of the reduction of 2-substituted cyclohexanones 1-6 with 4-substituted diisobutylaluminium phenoxides a-d has been investigated as a function of temperature. The high-temperature region is found to be dominated by hydride transfer, which is controlled by steric as well as electronic effects. However, at low temperatures the Meerwein-Ponndorf-Verley reaction gains in Importance. This phenomenon is quantified by an isoinversion relationship.
- Meyer-Stork, Markus A.,Haag, Dieter,Scharf, Hans-Dieter
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p. 593 - 595
(2007/10/03)
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- Nonenzymatic enantioselective acylation of racemic secondary alcohols catalyzed by a SnX2-Chiral diamine complex
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Kinetic resolution of racemic secondary alcohols has been achieved by the reaction with benzoyl halide in the presence of a SnX2-chiral diamine complex to afford the corresponding benzoate in good to excellent enantioselectivities.
- Oriyama, Takeshi,Hori, Yoko,Imai, Keisuke,Sasaki, Ryosuke
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p. 8543 - 8546
(2007/10/03)
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- Silica Gel Supported Zinc Borohydride. A Novel Reagent for Hydration of Unactivated Alkenes and Alkynes
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A simple and general procedure for hydration of unactivated alkenes and alkynes producing less substituted alcohols selectively has been achieved by the reaction of the corresponding alkenes or alkynes on silica gel support with zinc borohydride in 1,2-dimethoxyethane.
- Ranu, Brindaban C.,Sarkar, Arunkanti,Saha, Manika,Chakraborty, Rupak
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p. 6579 - 6584
(2007/10/02)
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- An Unusual Anti-Markovnikov Hydration of Alkenes with Titanium(III) Tetrahydroborates
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Titanium(III) tetrahydroborate formed by the reaction of titanium tetrachloride and benzyltriethylammonium borohydride (1:4) reacts with alkenes in dichloromethane (-20 deg C) very readily to yield directly the corresponding alcohols in excellent yields after a simple aqueous work up.
- Kumar, K. S. Ravi,Baskaran, S.,Chandrasekaran, S.
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p. 171 - 174
(2007/10/02)
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- An unusual regioselctive anti-Markovnikov hydration of alkenes with zinc borohydride on silica gel support
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An efficient and general procedure of regioselective anti-Markovnikov hydration of alkenes producing less-substituted alcohols has been achieved by a simple reaction of alkene on silica gel support with zinc borohydride in 1,2-dimethoxyethane.
- Ranu,Chakraborty,Saha
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p. 4659 - 4662
(2007/10/02)
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- An Internally Activated Tin Hydride with Enhanced Reducing Ability
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Tin hydride 1 is activated for nucleophilic hydride transfer and also for radical chain reduction, depending on solvent.The nucleophilic hydride pathway is favored in methanol, and 1 can be used as a selective reducing agent for ketones.Simple ketones are not reduced in aprotic solvents, but β-hydroxy ketones are activated internally by the hydroxyl group and can be reduced in THF with good control of stereochemistry, as in the conversion from 7 to 9 (30:1 9:8).A catalytic version of the nucleophilic hydride reductions in methanol has been developed using PhSiH3 as the stoichiometric hydride source.Radical chain dehalogenations can also be achieved with 1 at room temperature and without added radical initiators.Simple xanthates are not reduced efficiently in the absence of an initiator, but the reaction proceeds in the presence of AIBN.
- Vedejs, E.,Duncan, S. M.,Haight, A. R.
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p. 3046 - 3050
(2007/10/02)
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- A Facile Conversion of Alkenes to Alcohols with Benzyltriethylammonium Borohydride-Chlorotrimethylsilane
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A combination of benzyltrimethylammonium borohydride and chlorotrimethylsilane (1:1) in dichloromethane at 0 deg C has been found to be a convenient reagent system for the conversion of alkenes to alcohols, the hydroxy group of which is introduced in an anti-Markovnikov manner.
- Baskaran, Sundarababu,Gupta, Varsha,Chidambaram, Nallaperumal,Chandrasekaran, Srinivasan
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p. 903 - 904
(2007/10/02)
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- Solvolysis of cis- and trans-2-Phenylcyclohexyl-p-bromobenzene Sulphonate
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Die Solvolyse von cis- and trans-2-Phenyl-cyclohexyl-p-brombenzensulfonaten wurde in Essigsaeure, waessrigem Dioxan und waessrigem Ethanol untersucht und mit der des Cyclohexylsulfonatesters verglichen.In Essigsaeure liegt die Geschwindigkeit des cis-Isomeren gegenueber dem trans-Isomeren um den Faktor 5 hoeher, in waessrigem Dioxan und waessrigem Alkohol dagegen um den Faktor 10 bzw. 12.Produkte der Acetolyse sind hauptsaechlich Eliminierungsprodukte (1- und 3-Phenylcyclohexen 75 percent) und cis- und trans-Acetate (25 percent).In waessrigen Loesungsmitteln entstehen vorwiegend Eliminierungsprodukte (98 percent).Die Erhoehung der Geschwindigkeit des cis-Isomeren gegenueber der trans-Verbindung ist auf eine sterische Beschleunigung zurueckzufuehren.Ein solvatisiertes Ionenpaar wurde als Zwischenprodukt postuliert; fuer eine Phenylnachbargruppenwirkung ergab sich kein Hinweis.
- Youssef, Abdel-Hamid A.,Sharaf, Saber M.,Hegazy, Fatma M. El
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p. 725 - 734
(2007/10/02)
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- Properties of Bis(trifluoroacetoxy)borane as a Reducing Agent of Organic Compounds
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Reactions of bis(trifluoroacetoxy)borane-THF (1) with compounds containing representative organic functional groups were studied to determine the usefulness of 1 as a selective reducing agent.Reducible functionalities were indoles, ketones, aldehydes, imines, and compounds that readily generate carbocations in trifluoroacetic acid.Many functionalities were inert to 1.Epoxides and ortho esters suffered decomposition under the reaction conditions.Olefins and acetylenes were not hydroborated, and carboxylic acids were not reduced by 1.
- Maryanoff, Bruce E.,McComsey, David F.,Nortey, Samuel O.
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p. 355 - 360
(2007/10/02)
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- Formation of Alcohols from Alkenes with TiCl4-NaBH4
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The reaction of alkenes with TiCl4-NaBH4 in 1,2-dimethoxyethane afforded alcohols, the hydroxy group of which was introduced in an anti-Markovnikov direction.
- Kano, Shinzo,Tanaka, Yasuyuki,Hibino, Satoshi
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p. 414 - 415
(2007/10/02)
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