- Aluminum, indium, and mixed yttrium-lithium complexes supported by a chiral binap-based fluorinated dialkoxide: Structural features and heteroselective ROP of lactide
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The new chiral Binap-based fluorinated dialcohol proteo-ligand {ONNO}H2 has been prepared under its enantiomerically pure and racemic forms following reaction of (R)- or (rac)-1,1′-binaphthyl-2,2′-diamine with 5,5,5-trifluoro-4-hydroxy-4-(trifluoromethyl)pentan-2-one. The racemic proteo-ligand reacts with the trivalent metallic precursors AlEt2Cl and In(CH2SiMe3)3 to yield the complexes (rac)-{ONNO}AlCl (1) and (rac)-{ONNO}In(CH2SiMe3) (2), while the reaction of (R)-{ONNO}H2 with a 1:1 mixture of Y(N(SiMe3)2)3 and LiN(SiMe3)2 gives the enantiomerically pure heterobimetallic [((R)-{ONNO})2Y·Li] (3). Complex 3 acts as a single-component initiator for the near-perfect heteroselective ring-opening polymerization (ROP) of racemic lactide, yielding polymers with Pr up to 0.99 under mild conditions. It also produces syndiotactic-enriched polylactide (Pr = 0.80) by ROP of meso lactide.
- Maudoux, Nicolas,Roisnel, Thierry,Carpentier, Jean-Francois,Sarazin, Yann
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- The cross-aldol reaction of hexafluoroacetone (HFA) with ketones catalyzed by an acid
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The cross-aldol reactions of hexafluoroacetone (HFA) and ketones using an acid catalyst are reported. When concentrated sulfuric acid was employed as the catalyst, HFA reacted regioselectively with various ketones at 50-100 °C to give the aldol adducts (6) in good yields. The reaction is initiated by an acid-catalyzed transformation of the ketone into the corresponding enol that reacts with HFA. The obtained adducts (6) can be reduced with hydrogen under a Ru/C catalyst to lead to the corresponding fluorine-containing diols (13).
- Komata, Takeo,Matsunaga, Kei,Hirotsu, Yoshiki,Akiba, Shinya,Ogura, Katsuyuki
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- Convenient synthesis of mono- and di-β-hydroxy-β-bis(trifluoromethyl)-(di)imines from β-hydroxy-β-bis(trifluoromethyl)-ketones and (di)amines
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A series of novel β-hydroxy-β-bis(trifluoromethyl)-imines (2a-j) and di(β-hydroxy-β-bis(trifluoromethyl))-diimines (3a-f) were prepared in moderate to good yields via a simple two-step approach: first, β-hydroxy-β-bis(trifluoromethyl)-ketones (1a-c) were
- Marquet, Nicolas,Grunova, Ekaterina,Kirillov, Evgueni,Bouyahyi, Miloud,Thomas, Christophe M.,Carpentier, Jean-Fran?ois
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- STABLE ACID AMPLIFIER
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PROBLEM TO BE SOLVED: To provide an acid amplifier system which can be used for photolithography, especially for use in extreme UV (13.5 nm) or electron beam lithography. SOLUTION: This invention provides a sulfonic acid precursor compound represented by
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Paragraph 0144; 0146
(2018/12/01)
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- Fluorinated alkoxy-imino catalyst components
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This invention relates to fluorinated alkoxy-imino metallic complexes and their use in catalyst systems for the polymerisation or oligomerisation of ethylene and alpha-olefins.
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Page/Page column 4
(2008/06/13)
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- Processes for producing fluorine-containing 2,4-diols and their derivatives
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A process for producing a fluorine-containing 2,4-diol represented by the formula [4], wherein R1 represents a hydrogen atom or an acyclic or cyclic alkyl group having a carbon atom number of 1 to 7; R2 represents an acyclic or cyclic alkyl group having a carbon atom number of 1 to 7, a phenyl group, or a substituted phenyl group; and R1 and R2 are optionally bonded to each other to form a ring, includes reducing a hydroxy ketone represented by the formula [3], wherein R1 and R2 are defined as above, by hydrogen in the presence of a ruthenium catalyst.
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Page/Page column 8
(2008/06/13)
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