- Palladium-catalyzed anti-Markovnikov oxidative acetalization of activated olefins with iron(iii) sulphate as the reoxidant
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This paper discloses the efficient palladium-catalyzed anti-Markovnikov oxidative acetalization of activated terminal olefins with iron(iii) sulfate as the reoxidant. This methodology requires mild reaction conditions and shows high regioselectivity toward anti-Markovnikov products and compatibility with a wide range of functional groups. Iron(iii) sulphate was the sole reoxidant used in this method. Various olefins like vinylarenes, aryl-allylethers, aryl or benzyl acrylates and homoallylic alcohols all reacted well providing anti-Markovnikov acetals, some of which represent orthogonally functionalized 1,3- and 1,4-dioxygenated compounds.
- Fernandes, Rodney A.,Kumar, Praveen,Yadav, Sandhya S.
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p. 427 - 443
(2022/01/20)
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- Regioselective Wacker-Type Oxidation of Internal Olefins in tBuOH Using Oxygen as the Sole Oxidant and tBuONO as the Organic Redox Cocatalyst
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A regioselective Wacker-Tsuji oxidation of internal olefins in tBuOH has been developed using oxygen as the terminal oxidant and tert-butyl nitrite as the simple organic redox cocatalyst without the involvement of hazardous cocatalysts or harsh reaction conditions. A series of internal olefins bearing various functional groups can be oxidized to the corresponding substituted ketones in generally good yields with high regioselectivities.
- Huang, Qing,Li, Ya-Wei,Ning, Xiao-Shan,Jiang, Guo-Qing,Zhang, Xiao-Wei,Qu, Jian-Ping,Kang, Yan-Biao
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supporting information
p. 965 - 969
(2020/02/15)
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- Tuning Regioselectivity of Wacker Oxidation in One Catalytic System: Small Change Makes Big Step
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A regioselectivity switchable aerobic Wacker-Tsuji oxidation has been developed using catalytic tert-butyl nitrite as a simple organic redox cocatalyst. By solely switching the solvent, either substituted aldehydes or ketones could be prepared under mild
- Hu, Kang-Fei,Ning, Xiao-Shan,Qu, Jian-Ping,Kang, Yan-Biao
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p. 11327 - 11332
(2018/09/06)
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- 2-AMINO-1,3,4-THIADIAZINE AND 2-AMINO-1,3,4-OXADIAZINE BASED ANTIFUNGAL AGENTS
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The invention provides a compound which is a diazine of formula (I) or a tautomer thereof, or a pharmaceutically acceptable salt thereof, for use as an antifungal agent: (I) wherein X, N', C', A and E are as defined herein. The invention also provides a compound of Formula (I) as defined herein.
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Page/Page column 65
(2017/02/09)
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- Benzene C-H Etherification via Photocatalytic Hydrogen-Evolution Cross-Coupling Reaction
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Aryl ethers can be constructed from the direct coupling between the benzene C-H bond and the alcohol O-H bond with the evolution of hydrogen via the synergistic merger of photocatalysis and cobalt catalysis. Utilizing the dual catalyst system consisting of 3-cyano-1-methylquinolinum photocatalyst and cobaloxime, intermolecular etherification of arenes with various alcohols and intramolecular alkoxylation of 3-phenylpropanols with formation of chromanes are accomplished. These reactions proceed at remarkably mild conditions, and the sole byproduct is equivalent hydrogen gas.
- Zheng, Yi-Wen,Ye, Pan,Chen, Bin,Meng, Qing-Yuan,Feng, Ke,Wang, Wenguang,Wu, Li-Zhu,Tung, Chen-Ho
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supporting information
p. 2206 - 2209
(2017/05/12)
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- Tert-Butyl Nitrite: Organic Redox Cocatalyst for Aerobic Aldehyde-Selective Wacker-Tsuji Oxidation
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An aldehyde-selective aerobic Wacker-Tsuji oxidation is developed. Using tert-butyl nitrite as a simple organic redox cocatalyst instead of copper or silver salts, a variety of aldehydes were achieved as major products in up to 30/1 regioselectivity as well as good to high yields at room temperature.
- Ning, Xiao-Shan,Wang, Mei-Mei,Yao, Chuan-Zhi,Chen, Xian-Min,Kang, Yan-Biao
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supporting information
p. 2700 - 2703
(2016/06/15)
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- ALDEHYDE-SELECTIVE WACKER-TYPE OXIDATION OF UNBIASED ALKENES
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This disclosure is directed to methods of preparing organic aldehydes, each method comprising contacting a terminal olefin with an oxidizing mixture comprising: (a) a dichloro-palladium complex; (b) a copper complex; (c) a source of nitrite; under aerobic reaction conditions sufficient to convert at least a portion of the terminal olefin to an aldehyde.
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Paragraph 0178-0183
(2014/10/29)
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- Catalyst-controlled wacker-type oxidation: Facile access to functionalized aldehydes
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The aldehyde-selective oxidation of alkenes bearing diverse oxygen groups in the allylic and homoallylic position was accomplished with a nitrite-modified Wacker oxidation. Readily available oxygenated alkenes were oxidized in up to 88% aldehyde yield and as high as 97% aldehyde selectivity. The aldehyde-selective oxidation enabled the rapid, enantioselective synthesis of an important pharmaceutical agent, atomoxetine. Finally, the influence of proximal functional groups on this anti-Markovnikov reaction was explored, providing important preliminary mechanistic insight.
- Wickens, Zachary K.,Skakuj, Kacper,Morandi, Bill,Grubbs, Robert H.
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supporting information
p. 890 - 893
(2014/02/14)
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- Process for the Preparation of 4-(4-hydroxyphenyl)butan-2-one Using Solid Acid Clay Catalyst
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Solid acid catalyst such as acid activated-Montmorillonite clay composite has been developed by modifying the Na-Montmorillonite clay with acid (HCl) treatment for different periods such as 5 minutes to about 4 hours and activating at about 12O° C. for about 2 hours. Friedel Crafts alkylation reaction between phenol and 4-hydroxybutan-2-one in presence of the acid activated Montmorillonite clay catalysts exhibiting layered clay structures (basal spacing d001 ranging from about 10 to 13.5 ?), high surface area (250-400 m2/g), highly porous {micropores in the range 5 to 15 ? and mesopores in the range 30 to 80 ?}, average pore volume 0.2 to 0.65 cc/g, and surface acidity in the range 0.4-0.6 mmol/g; under constant stirring and at pressure of 1-15 bar, temperature 100-15O° C. for a period of about 12-24 hours produces 4-(4-hydroxyphenyl)butan-2-one (Raspberry ketone) exhibiting conversion about 35-55% and high selectivity in the range 75-81%.
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Page/Page column 5
(2011/10/31)
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- The ionic liquid ethyltri-n-butylphosphonium tosylate as solvent for the acid-catalysed hetero-Michael reaction
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A new and convenient method for the acid-catalysed Michael addition reactions of alcohols, thiols and amines to methyl vinyl ketone has been developed using the ionic liquid ethyltri-n-butylphosphonium tosylate. The reaction conditions are mild and obviat
- Karodia, Nazira,Liu, Xihan,Ludley, Petra,Pletsas, Dimitrios,Stevenson, Grace
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p. 11039 - 11043
(2007/10/03)
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- Phosphine-catalyzed hydration and hydroalkoxylation of activated olefins: Use of a strong nucleophile to generate a strong base
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The direct addition of water and a variety of alcohols to activated olefins was observed in the presence of nucleophilic phosphine catalysts. Unlike existing methods, the reactions proceed at room temperature and in the absence of transition metals, or strong acids or bases. The use of simple commercially available catalysts makes this an attractive method for the preparation of β-hydroxy and β-alkoxy substrates, which are prevalent targets and intermediates in organic synthesis. The scope and mechanism of this reaction has been explored, and the compound that acts as the resting state of the catalyst was synthesized independently. Our mechanism also suggests the possibility of extending the scope of this reactivity to other classes of nucleophiles. Copyright
- Stewart, Ian C.,Bergman, Robert G.,Toste, F. Dean
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p. 8696 - 8697
(2007/10/03)
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- Cation-Exchanged Montmorillonite-Catalyzed Facile Friedel-Crafts Alkylation of Hydroxy and Methoxy Aromatics with 4-Hydroxybutan-2-one To Produce Raspberry Ketone and Some Pharmaceutically Active Compounds
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The Friedel-Crafts alkylation of hydroxy and methoxy aromatics with 4-hydroxybutan-2-one (γ-KB) in the presence of a cation-exchanged montmorillonite (M(n+)-mont; M(n+) = Zr(4+), Al(3+), Fe(3+), and Zn(2+)) was investigated.Phenol was C-alkylated regiospecifically with γ-KB in the presence of Zr(4+)-, Al(3+)-, or Fe(3+)-mont to produce 4-(4-hydroxyphenyl)butan-2-one (raspberry ketone) in 31-35percent GLC yield.Anisole, 2-methoxynaphthalene, and 1-methoxynaphthalene were regiospecifically C-alkylated to produce 4-(4-methoxyphenyl)butan-2-one, 4-(2-methoxy-1-naphthyl)butan-2-one (pharmaceutically active), and 4-(4-methoxy-1-naphthyl)butan-2-one, respectively.Al(3+)- and Fe(3+)-mont were the most effective catalysts in these cases (13-58percent isolated yield). γ-KB could be used as an alkylating agent instead of the highly toxic 3-buten-2-one (MVK) which also polymerizes easily.
- Tateiwa, Jun-ichi,Horiuchi, Hiroki,Hashimoto, Keiji,Yamauchi, Takayoshi,Uemura, Sakae
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p. 5901 - 5904
(2007/10/02)
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- Rearrangement Alkyl Phenyl Ethers to Alkylphenols in the Presence of Cation-exchanged Montmorillonite (Mn+-Mont)
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The rearrangement of alkyl phenyl ethers such as 4-phenoxybutan-2-one 1, 1-phenoxybutane 2a, 2-phenoxybutane 2b, 2-methyl-2-phenoxypropane 2c and phenoxycyclohexane 2d have been investigated in the presence of cation-exchanged montmorilonite (Mn+-mont; Mn+ = Zr4+, Al3+, Fe3+ and Zn2+).The ether 1 rearranged to 4-(4-hydroxyphenyl)butan-2-one 3 (raspberry ketone), the odour source of rasprerry, in 16-34percent GLC yield, where Zn2+-mont was the most effective catalyst.Similarly, other ethers 2a-d rearranged to the corresponding alkylphenols in up to 75percent isolated yield with good product selectivity, Al3+-mont being the catalyst of choice.Al3+-Mont was regenerated and resulted in the rearrangement of 2b, 2c and 2d.
- Tateiwa, Jun-ichi,Nishimura, Takahiro,Horiuchi, Hiroki,Uemura, Sakae
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p. 3367 - 3372
(2007/10/02)
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- C-ALKYLATION OF PHENOLS WITH METHYL VINYL KETONE IN THE PRESENCE OF BASES
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The C-alkylation of phenols with methyl vinyl ketone in alcohols in the presence of alkali-metal alcoholates at -60 to +40 deg C was investigated by the PMR method.At -30 to 0 deg C methyl vinyl ketone reacts with primary alcohols with the formation of β-alkoxy-2-butanones, the subsequent reaction of which with 2,6-di-tert-butylphenol at 20-40 deg C by a mechanism of nucleophilic substitution leads to the formation of 4-(3,5-di-tert-butyl-4-hydroxyphenyl)-2-butanone.The composition of the products from the reaction of 2,6-di-tert-butylphenol with methyl vinyl ketone and β-methoxy-2-butanone was studied.
- Titova, T. F.,Krysin, A. P.,Shakirov, M. M.,Mamatyuk, V. I.
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p. 294 - 301
(2007/10/02)
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