- CATALYSTS
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A complex of formula (I) wherein M is zirconium or hafnium; each X independently is a sigma ligand; L is a divalent bridge selected from -R'2C-, -R'2C-CR'2-, -R'2Si-, -R'2Si-SiR'2-, -R'2Ge-, wherein each R' is independently a hydrogen atom or a C1-C20-hydrocarbyl group optionally containing one or more silicon atoms or heteroatoms of Group 14-16 of the periodic table or fluorine atoms, and optionally two R' groups taken together can form a ring; R2 and R2' are each independently a C1-C20 hydrocarbyl group, -OC1- hydrocarbyl group or -SC1-20 hydrocarbyl group; R5 is a -OC1-20 hydrocarbyl group or -SC1-20 hydrocarbyl group, said R5 group being optionally substituted by one or more halo groups; R5' is hydrogen or a C1-20 hydrocarbyl group; -OC1-20 hydrocarbyl group or -SC1-20 hydrocarbyl group; said C1-20 hydrocarbyl group being optionally substituted by one or more halo groups; R6 and R6' are each independently a C1-20 hydrocarbyl group; -OC1-20 hydrocarbyl group or -SC1-20 hydrocarbyl group; each R1 and R1' are independently -CH2Rx wherein Rx are each independently H, or a C1-20 hydrocarbyl group, optionally containing heteroatoms.
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Page/Page column 73; 74
(2018/06/06)
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- Practical Aerobic Oxidation of Alcohols: A Ligand-Enhanced 2,2,6,6-Tetramethylpiperidine-1-oxy/Manganese Nitrate Catalyst System
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A highly efficient, ligand-enhanced 2,2,6,6-tetramethylpiperidine-1-oxy (TEMPO)/Mn(NO3)2 catalyst system for the aerobic oxidation of alcohols is described. From the series of coordinating ligands studied herein, 2-picolinic acid (PyCOOH) improves the catalytic activity of TEMPO/Mn(NO3)2 remarkably. Under ambient air at room temperature in acetic acid, the ligand-enhanced catalyst converts aliphatic and benzylic primary alcohols that bear various functional groups into their respective aldehydes with near quantitative conversions. The applicability of the catalyst for convenient preparative synthesis was demonstrated by conducting oxidations on a gram scale. A change of TEMPO to the sterically less demanding 9-azabicyclo[3.3.1]nonane N-oxyl results in a Mn catalyst that is also able to oxidize secondary alcohols to ketones. Mechanistic studies showed that alcohols are oxidized by the oxoammonium cation derived from the nitroxyl radical. The active oxidant is regenerated by Mn(NO3)2, and this process is greatly promoted by the coordination of PyCOOH to Mn.
- Lagerblom, Kalle,Lagerspets, Emi,Keskiv?li, Juha,Cook, Chris,Ekholm, Filip,Parviainen, Arno,Repo, Timo
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p. 3880 - 3887
(2017/09/28)
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- CATALYST
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A catalyst in solid particulate form free from an external carrier material comprising (i) a complex of formula (I) wherein M is zirconium or hafnium; each X is a sigma ligand; L is a divalent bridge selected from -R'2C-, -R'2C-CR'2-, -R'2Si-, -R'2Si-Si R'2-, -R'2 Ge-, wherein each R' is independently a hydrogen atom, C1-20-alkyl, tri(C1-20-alkyl)silyl, C6-20-aryl, C7-20-arylalkyl or C7-20-alkylaryl; R2 is a C1-20-hydrocarbyl radical; R2' is a C1-20-hydrocarbyl radical;R6 is a linear or branched aliphatic C1-20-hydrocarbyl group, SR9or OSR9;R6' is a linear or branched aliphatic C1-20-hydrocarbyl group, SR9'or OR9'; with the proviso that neither R6 or R6' represents a group having a quaternary carbon atom directly attached to the indenyl ring; R9 is a C1-20-hydrocarbyl group;R9' is a C1-20-hydrocarbyl group; Ar is a C6-12-aryl or C5-12-heteroaryl group optionally carrying one or more substituents R8; Ar' is a C6-12-aryl or C5-12-heteroaryl group optionally carrying one or more substituents R8';each R8 is a C1-20-hydrocarbyl group;each R8' is a C1-20 -hydrocarbyl group;wherein at least two of R2 and R2'; R6 and R6'; or Ar and Ar' are the same;and (ii) a cocatalyst comprising a compound of a group 13 metal, e.g. Al or boron.
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Page/Page column 35
(2014/07/08)
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- LOXOPROFEN DERIVATIVE AND PHARMACEUTICAL PREPARATION CONTAINING THE SAME
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There is provided a novel loxoprofen derivative that has no side effect such as a gastrointestinal disorder and also has excellent anti-inflammatory and analgesic effects and is represented by the following formula (I) or (II): (wherein R1 and
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Page/Page column 3-4
(2012/02/01)
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- Synthesis and biological evaluation of loxoprofen derivatives
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Non-steroidal anti-inflammatory drugs (NSAIDs) achieve their anti-inflammatory actions through an inhibitory effect on cyclooxygenase (COX). Two COX subtypes, COX-1 and COX-2, are responsible for the majority of COX activity at the gastrointestinal mucosa and in tissues with inflammation, respectively. We previously suggested that both gastric mucosal cell death due to the membrane permeabilization activity of NSAIDs and COX-inhibition at the gastric mucosa are involved in NSAID-induced gastric lesions. We have also reported that loxoprofen has the lowest membrane permeabilization activity among the NSAIDs we tested. In this study, we synthesized a series of loxoprofen derivatives and examined their membrane permeabilization activities and inhibitory effects on COX-1 and COX-2. Among these derivatives, 2-{4′-hydroxy-5-[(2-oxocyclopentyl)methyl]biphenyl-2-yl}propanoate 31 has a specificity for COX-2 over COX-1. Compared to loxoprofen, oral administration of 31 to rats produced fewer gastric lesions but showed an equivalent anti-inflammatory effect. These results suggest that 31 is likely to be a therapeutically beneficial and safer NSAID.
- Yamakawa, Naoki,Suemasu, Shintaro,Matoyama, Masaaki,Tanaka, Ken-Ichiro,Katsu, Takashi,Miyata, Keishi,Okamoto, Yoshinari,Otsuka, Masami,Mizushima, Tohru
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scheme or table
p. 3299 - 3311
(2011/07/08)
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- Method for producing halogen-substituted aromatic aldehyde
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In the production method of the invention, a halogen-substituted aromatic compound is reacted with carbon monoxide in the presence of hydrogen fluoride and boron trifluoride into a corresponding halogen-substituted aromatic aldehyde. By the use of hydrogen fluoride and boron trifluoride, the para position to halogen atom is selectively formylated to provide the halogen-substituted aromatic aldehyde in high yields in a short reaction time even at temperatures lower than room temperature.
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Page/Page column 6
(2008/06/13)
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- Vilsmeier reaction studies on some α,β-unsaturated alkenones
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α,β-Unsaturated alkenones (1a-g) are converted into chlorobenzenemono-, di- and tricarboxaldehydes (2a-h) under Vilsmeier reaction conditions.Besides six known chlorobenzaldehydes the route affords, in a one-pot reaction, two new members of this class of compounds, 3-methyl-(2d) and 3,5-dimethyl-(2h)-2-chlorobenzaldehydes.
- Sreenivasulu, M.,Rao, G. S. Krishna
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p. 494 - 495
(2007/10/02)
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