- Chromium-Salen Complex/Nitroxyl Radical Cooperative Catalysis: A Combination for Aerobic Intramolecular Dearomative Coupling of Phenols
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We describe an aerobic intramolecular dearomative coupling reaction of tethered phenols using a catalytic system consisting of a chromium-salen (Cr-salen) complex combined with a nitroxyl radical. This novel catalytic system enables formation of various spirocyclic dienone products including those unable to be accessed by previously reported methods efficiently under mild reaction conditions.
- Nagasawa, Shota,Fujiki, Shogo,Sasano, Yusuke,Iwabuchi, Yoshiharu
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p. 6952 - 6968
(2021/05/29)
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- P-Hydroxyphenacyl photoremovable protecting groups Robust photochemistry despite substituent diversity
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A broadly based investigation of the effects of a diverse array of substituents on the photochemical rearrangement of p-hydroxyphenacyl esters has demonstrated that common substituents such as F, MeO, CN, CO2R, CONH2, and CH3 have little effect on the rate and quantum efficiencies for the photo-Favorskii rearrangement and the release of the acid leaving group or on the lifetimes of the reactive triplet state. A decrease in the quantum yields across all substituents was observed for the release and rearrangement when the photolyses were carried out in buffered aqueous media at pHs that exceeded the ground-state pKa of the chromophore where the conjugate base is the predominant form. Otherwise, substituents have only a very modest effect on the photoreaction of these robust chromophores.
- Givens, Richard S.,Stensrud, Kenneth,Conrad, Peter G.,Yousef, Abraham L.,Perera, Chamani,Senadheera, Sanjeewa N.,Heger, Dominik,Wirz, Jakob
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scheme or table
p. 364 - 384
(2011/06/22)
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- PESTICIDAL SUBSTITUTED PHENYLETHERS
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The invention relates to the use of phenylether derivatives of formula (I), to compositions thereof for the control of pests, including arthropods and helminths.
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Page/Page column 42; 45
(2008/06/13)
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- SUBSTITUTED PHENOXY-AMINOPROPANOLS
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Substituted phenoxy-aminopropanols of the formula STR1 wherein R is a branched-chain alkyl of 3 or 4 carbon atoms, R 1 is hydrogen, halogen or lower alkyl and R 2 and R 3, independently, are hydrogen, halogen, lower alkyl, lower alkoxy or lower alkylthio, and pharmaceutically acceptable acid addition salts thereof, are described. A process for their preparation, as well as pharmaceutical preparations containing them are also described. The compounds of formula I and their salts possess cardioselective β-adrenergic blocking activity and antihypertensive activity.
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- β1-Selective Adrenoceptor Antagonists. 2. 4-Ether-Linked Phenoxypropanolamines
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A series of 4-substituted phenoxypropanolamines was prepared and examined for β-adrenoceptor activity.Some of the compounds, especially the oxy>ethoxy>phenoxy>propanolamines (14, 15, and 24), showed potent β1-blo
- Machin, Peter J.,Hurst, David N.,Bradshaw, Rachel M.,Blaber, Leslie C.,Burden, David T.,et al.
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p. 1570 - 1576
(2007/10/02)
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