- Site-Selective Defluorinative sp3C-H Alkylation of Secondary Amides
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A site-selective defluorinative sp3 C-H alkylation of secondary amides that rapidly and reliably incorporates gem-difluoroalkene motifs into previously unfunctionalized sp3 sites is disclosed. This protocol is distinguished by its mild conditions, wide scope, and exquisite site-selectivity, thus unlocking a new platform to introduce carbonyl isosteres at saturated hydrocarbon sites.
- Day, Craig S.,Martin, Ruben,Yue, Wen-Jun
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- Photoredox/Hydrogen Atom Transfer Cocatalyzed C-H Difluoroallylation of Amides, Ethers, and Alkyl Aldehydes
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Herein, we report a method that combines hydrogen atom transfer and photoredox catalysis to achieve the dehydrogenative difluoroallylation of amides, ethers, and alkyl aldehydes. This operationally convenient method transforms a broad scope of substrates into the corresponding gem-difluoroalkenes via the construction of C(sp3)-C(sp3) or C(sp3)-C(sp2) bonds. Excellent functional group compatibility and high selectivity make this method have a wide range of substrate types and render it suitable for late-stage modification of pharmaceutical intermediates.
- Guo, Yuan-Qiang,Wu, Yifan,Wang, Ruiguo,Song, Hongjian,Liu, Yuxiu,Wang, Qingmin
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supporting information
p. 2353 - 2358
(2021/04/05)
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- Photoredox relay-catalyzedgem-difluoroallylation of alkyl iodides
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Herein, a new example of relay catalysis, using a combination of Mn2(CO)10and an iridium-based photocatalyst, is reported. In our relay catalytic reaction, the Mn catalyst and iridium-based photocatalyst catalyze the reaction at different stages in the desired sequence under the same reaction conditions, and do not inhibit each other. This convenient method transforms a broad scope of alkyl iodides into the correspondinggem-difluoroalkenesviaC(sp3)-C(sp3) bond construction. The protocol has good functional group tolerance and is suitable for the late-stage modification of multifunctional complex molecules.
- Cao, Yunpeng,Guo, Yuanqiang,Liu, Yuxiu,Song, Hongjian,Wang, Qingmin
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supporting information
p. 9768 - 9771
(2021/09/30)
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- Visible-Light-Driven Sulfonation of α-Trifluoromethylstyrenes: Access to Densely Functionalized CF3-Substituted Tertiary Alcohol
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Reported herein is a visible-light-induced sulfonation of α-trifluoromethylstyrenes with sodium sulfinates, which provides a series of α-trifluoromethyl-β-sulfonyl tertiary alcohols. This new synthetic protocol is enabled by a charge-transfer complex between oxygen and sulfinates, featuring broad substrate scope and scalability. Excellent functional group compatibility and chemoselectivity render this method suitable for sulfonation of pharmaceutically relevant molecules. In the presence of D2O, deuteriotrifluorinated products were also obtained, further demonstrating the flexibility and synthetic potentials of this strategy.
- Chen, Yi-Xuan,Wang, Zhu-Jun,Xiao, Jun-An,Chen, Kai,Xiang, Hao-Yue,Yang, Hua
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supporting information
p. 6558 - 6562
(2021/08/23)
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- Electrochemical heterodifunctionalization of α-CF3alkenes to access α-trifluoromethyl-β-sulfonyl tertiary alcohols
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An unprecedented electrochemical heterodifunctionalization of α-CF3alkenes with benzenesulfonyl hydrazides was accomplished in this work, wherein a β-sulfonyl and a α-hydroxyl group were simultaneously incorporated across the olefinic double bond in a single operation. Consequently, a series of potentially medicinally valuable and densely functionalized α-trifluoromethyl-β-sulfonyl tertiary alcohols were assembled under mild conditions. Electrochemically-driven oxidative 1,2-difunctionlization of electron-deficient alkenes well obviates the need for oxidizing reagents, thus rendering this protocol more eco-friendly.
- Chen, Kai,Duan, Xin-Yu,Gao, Jie,Guan, Jian-Ping,Liu, Fang,Xiang, Hao-Yue,Xiao, Jun-An,Yang, Hua,Ye, Zhi-Peng
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supporting information
p. 8969 - 8972
(2021/09/10)
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- Glycosyl-Radical-Based Synthesis of C-Alkyl Glycosides via Photomediated Defluorinative gem-Difluoroallylation
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We have developed a stereoselective, glycosyl radical-based method for the synthesis of C-alkyl glycosides via a photomediated defluorinative gem-difluoroallylation reaction. We demonstrate for the first time that glycosyl radicals, generated from glycosyl bromides, can readily participate in a photomediated radical polar crossover process, affording a diverse array of gem-difluoroalkene containing C-glycosides. Notable features of this method include scalability, mild conditions, broad substrate scope, and suitability for the late-stage modification of complex molecules.
- Li, Cai-Yi,Ma, Yue,Lei, Zhi-Wei,Hu, Xiang-Guo
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supporting information
p. 8899 - 8904
(2021/11/20)
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- Biocatalytic Strategy for the Highly Stereoselective Synthesis of CHF2-Containing Trisubstituted Cyclopropanes
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The difluoromethyl (CHF2) group has attracted significant attention in drug discovery and development efforts, owing to its ability to serve as fluorinated bioisostere of methyl, hydroxyl, and thiol groups. Herein, we report an efficient biocat
- Carminati, Daniela M.,Decaens, Jonathan,Couve-Bonnaire, Samuel,Jubault, Philippe,Fasan, Rudi
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supporting information
p. 7072 - 7076
(2021/02/27)
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- One-pot synthesis of α-trifluoromethylstyrenes from aryl ketones and the Ruppert–Prakash reagent
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A new synthesis of α-trifluoromethylstyrenes from aromatic ketones and (trifluoromethyl) trimethylsilane is described. The reaction involves nucleophilic trifluoromethylation and elimination of trimethylsilanol, which are performed within one reaction fla
- Dilman, Alexander D.,Levin, Vitalij V.
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p. 684 - 685
(2021/11/26)
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- Visible-Light-Induced Deoxygenation/Defluorination Protocol for Synthesis of γ,γ-Difluoroallylic Ketones
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Herein, we describe an efficient, practical photocatalytic deoxygenation/defluorination protocol for the synthesis of γ,γ-difluoroallylic ketones from commercially available aromatic carboxylic acids, triphenylphosphine, and α-trifluoromethyl alkenes. The protocol has good functional group tolerance and a broad substrate scope. Using this method, we accomplished the late-stage functionalization of several bioactive molecules.
- Guo, Yuan-Qiang,Wang, Ruiguo,Song, Hongjian,Liu, Yuxiu,Wang, Qingmin
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supporting information
p. 709 - 713
(2020/01/31)
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- Photoinduced Single-Electron Transfer as an Enabling Principle in the Radical Borylation of Alkenes with NHC–Borane
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A photoinduced SET process enables the direct B?H bond activation of NHC–boranes. In contrast to common hydrogen atom transfer (HAT) strategies, this photoinduced reaction simply takes advantage of the beneficial redox potentials of NHC–boranes, thus obviating the need for extra radical initiators. The resulting NHC–boryl radical was used for the borylation of a wide range of α-trifluoromethylalkenes and alkenes with diverse electronic and structural features, providing facile access to highly functionalized borylated molecules. Labeling and photoquenching experiments provide insight into the mechanism of this photoinduced SET pathway.
- Chen, Xiao-Qing,Hu, Yuan-Zhuo,Song, Dan,Xia, Peng-Ju,Xiang, Hao-Yue,Xiao, Jun-An,Yang, Hua,Ye, Zhi-Peng
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supporting information
p. 6706 - 6710
(2020/02/05)
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- Visible-Light-Induced Radical Defluoroborylation of Trifluoromethyl Alkenes: An Access to gem-Difluoroallylboranes
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A photoredox-catalyzed defluoroborylation of trifluoromethyl alkenes with N-heterocyclic carbene boranes is described for the synthesis of gem-difluoroallylboranes. This protocol exhibits a broad substrate scope and good functional group compatibility, which enables the late-stage functionalization of structurally complex compounds. Further transformations of the defluoroborylation products to valuable CF2-containing molecules are also demonstrated. (Figure presented.).
- Chen, Guojun,Wang, Liling,Liu, Xiaozu,Liu, Peijun
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supporting information
p. 2990 - 2996
(2020/06/10)
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- The coupling of alkylboronic acids with α-(trifluoromethyl)styrenes by Lewis base/photoredox dual catalysis
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Under Lewis base/photoredox dual catalysis, the defluorinative alkylation of alkylboronic acids with α-(trifluoromethyl)styrenes has been reported. In this system, both primary and secondary alkyl radicals produced by alkylboronic acids can react with α-(trifluoromethyl)styrenes to generate alkylated gem-difluoroalkenes. In general, the method has mild conditions, a wide substrate scope, and good functional group tolerance, which provides a new route for the synthesis of gem-difluoroalkenes.
- Chen, Yuefeng,Ni, Niannian,Cheng, Dongping,Xu, Xiaoliang
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supporting information
(2020/09/21)
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- Photocatalytic, Phosphoranyl Radical-Mediated N-O Cleavage of Strained Cycloketone Oximes
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A photoinduced, phosphoranyl radical-mediated protocol for the direct N-O cleavage of strained cycloketone oximes via a polar/SET crossover process was developed for the first time. This visible-light-driven direct N-O activation mode for oxime offers beneficial features such as streamlined synthetic process and versatile photochemical reactivities. Consequently, the alkenes and α-trifluoromethyl alkenes with varied electronic and structural features acted as competent radical receptors in this protocol, enabling facile accesses to a range of elongated cyano and/or gem-difluoroalkene-bearing compounds.
- Xia, Peng-Ju,Ye, Zhi-Peng,Hu, Yuan-Zhuo,Song, Dan,Xiang, Hao-Yue,Chen, Xiao-Qing,Yang, Hua
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supporting information
p. 2658 - 2662
(2019/04/25)
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- Synthesis of ethyl 5-aryl-5-(trifluoromethyl)-4,5-dihydroisoxazole-3-carboxylates, exhibiting plant growth-regulating properties
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A convenient method for the synthesis of high-boiling-point α-(trifluoromethyl)styrenes was proposed. The regioselective synthesis of a series of ethyl 5-aryl-5-(trifluoromethyl)-4,5- dihydroisoxazole-3-carboxylates was conducted by the reaction of ethyl
- Sigan,Golubev,Belyaeva,Gorfinkel,Kagramanov,Spiridonov, Yu. Ya.,Chkanikov
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- Synthesis of gem-Difluoroallylboronates via FeCl2-Catalyzed Boration/β-Fluorine Elimination of Trifluoromethyl Alkenes
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The first ferrous chloride catalyzed boration/β-fluorine elimination of trifluoromethyl alkenes is described. Thus, a full range of gem-difluoroallylboronates were obtained in high yield under mild conditions. As an important fluorinated building block, gem-difluoroallylboronate can be readily converted into diverse difluoro-substituted species.
- Liu, Yang,Zhou, Yuhan,Zhao, Yilong,Qu, Jingping
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supporting information
p. 946 - 949
(2017/02/26)
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- Palladium-Catalyzed Trimethylenemethane Cycloaddition of Olefins Activated by the δ-Electron-Withdrawing Trifluoromethyl Group
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α-Trifluoromethyl-styrenes, trifluoromethyl-enynes, and dienes undergo palladium-catalyzed trimethylenemethane cycloadditions under mild reaction conditions. The trifluoromethyl group serves as a unique δ-electron-withdrawing group for the activation of the olefin toward the cycloaddition. This method allows for the formation of exomethylene cyclopentanes bearing a quaternary center substituted by the trifluoromethyl group, compounds of interest for the pharmaceutical, agrochemical, and materials industries. In the diene series, the cycloaddition operates in a [3 + 4] and/or [3 + 2] manner to give rise to seven- and/or five-membered rings. This transformation greatly improves the scope of the TMM cycloaddition technology and provides invaluable insights into the reaction mechanism.
- Trost, Barry M.,Debien, Laurent
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supporting information
p. 11606 - 11609
(2015/09/28)
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- Synergistic interplay of a non-heme iron catalyst and amino acid coligands in H2O2 activation for asymmetric epoxidation of α-alkyl-substituted styrenes
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Highly enantioselective epoxidation of α-substituted styrenes with aqueous H2O2 is described by using a chiral iron complex as the catalyst and N-protected amino acids (AAs) as coligands. The amino acids synergistically cooperate with the iron center in promoting an efficient activation of H2O2 to catalyze epoxidation of this challenging class of substrates with good yields and stereoselectivities (up to 97% ee) in short reaction times.
- Cuss, Olaf,Ribas, Xavi,Lloret-Fillol, Julio,Costas, Miquel
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supporting information
p. 2729 - 2733
(2015/03/04)
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- Double C-F bond activation through β-fluorine elimination: Nickel-mediated [3+2] cycloaddition of 2-trifluoromethyl-1-alkenes with alkynes
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The nickel-mediated [3+2] cycloaddition of 2-trifluoromethyl-1-alkenes with alkynes afforded fluorine-containing multi-substituted cyclopentadienes in a regioselective manner. This reaction involves the consecutive two C-F bond cleavage of a trifluoromethyl or a pentafluoroethyl group through β-fluorine elimination.
- Ichitsuka, Tomohiro,Fujita, Takeshi,Arita, Tomohiro,Ichikawa, Junji
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supporting information
p. 7564 - 7568
(2014/08/05)
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- Chiral imidate-ferrocenylphosphanes: Synthesis and application as P,N-ligands in iridium(i)-catalyzed hydrogenation of unfunctionalized and poorly functionalized olefins
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A small library of chiral imidate-ferrocenylphosphane ligands was efficiently synthesized (8 examples) and evaluated in the iridium(i)-catalyzed hydrogenation of unfunctionalized and poorly functionalized olefins. These catalysts perform very well in a range of examples (yields and ee's up to 100%).
- Bert, Katrien,No?l, Timothy,Kimpe, Wim,Goeman, Jan L.,Van Der Eycken, Johan
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supporting information
p. 8539 - 8550
(2013/01/15)
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- Efficient trifluoromethylation of activated and non-activated alkenyl halides by using (trifluoromethyl)trimethylsilane
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An efficient method for the trifluoromethylation of halogenated double bonds by using in situ generated "trifluoromethyl copper" is described. Herein, the most common trifluoromethyl source, (trifluoromethyl) trimethylsilane, was converted selectively int
- Hafner, Andreas,Braese, Stefan
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supporting information; experimental part
p. 3044 - 3048
(2012/01/02)
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- Syntheses of mono-, di-, and trifluorinated styrenic monomers
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Concise syntheses of gram quantities of three fluorinated -methylstyrenic monomers suitable for polymerisation studies are disclosed, all based on the use of reasonably priced commercially available starting materials and reagents. Georg Thieme Verlag Stuttgart New York.
- Walkowiak, Justyna,Del Campo, Teresa Martinez,Ameduri, Bruno,Gouverneur, Veronique
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experimental part
p. 1883 - 1890
(2010/08/20)
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- Synthesis of α-trifluoromethylstyrene derivatives via Ni-catalyzed cross-coupling of 2-bromo-3,3,3-trifluoropropene and aryl Grignard reagents
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The Ni-catalyzed cross-coupling of 2-bromo-3,3,3-trifluoropropene and aryl Grignard reagents was investigated. When NiCl2(PPh3)2 was used as a catalyst, the highest yield of α-trifluoromethylstyrene (89%) from 2-bromo-3,3,
- Kobayashi, Osamu,Uraguchi, Daisuke,Yamakawa, Tetsu
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experimental part
p. 591 - 594
(2009/11/30)
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- Synthesis of gem-difluoroalkenes via β-fluoride elimination of organorhodium(I)
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Treatment of α-(trifluoromethyl)styrenes with arylboronic esters and MeMgCl in the presence of a rhodium(I) catalyst affords gem-difluoroalkenes. The reaction proceeds through the addition of arylrhodium(I) species across the electron-deficient carbon-carbon double bond and the subsequent β-fluoride elimination. Copyright
- Miura, Tomoya,Ito, Yoshiteru,Murakami, Masahiro
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supporting information; experimental part
p. 1006 - 1007
(2009/04/06)
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- 6-AMINO(AZA)INDANE COMPOUNDS SUITABLE FOR TREATING DISORDERS THAT RESPOND TO MODULATION OF THE DOPAMINE D3 RECPTOR
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The present invention relates to 6-amino(aza)indane compound of the formula (I) Wherein Ar is phenyl or an aromatic 5-or 6-membered C-bound heteroaromatic radical, wherein Ar may carry 1 radical Ra and wherein Ar may also carry I or 2 radicals Rb; X is N or CH; E is CR6R7 or NR 3; R1 is C 1-C4-alkyl, C3-C4-cycloalkyl, C3-C4-cycloalkylmethyl, C3-C4-alkenyl, fluorinated C1-C4-alkyl, fluorinated C3-C4-cycloalkyl, fluorinated C3-C4-cycloalkylmethyl, fluorinated C3-C4-alkenyl, formyl or C1-C3-alkylcarbonyl; R1a is H or R1a and R2 or R1a and R2a together are (CH2)n with n being 1, 2, 3 or 4; R2 and R2a each independently are H, CH3, CH2F, CHF2 or CF3; R3 is H or C,-C4-alkyl; and the physiologically tolerated acid addition salts of these compounds. The invention also relates to pharmaceutical compositions comprising at least one compound of the formula (I) or a pharmaceutically acceptable salt thereof and to a method for treating a medical disorder susceptible to treatment with a dopamine D3 receptor ligand, said method comprising administering an effective amount of at least one compound of the formula (I) or a pharmaceutically acceptable salt thereof.
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Page/Page column 78
(2008/06/13)
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- AMINOETHYLAROMATIC COMPOUNDS SUITABLE FOR TREATING DISORDERS THAT RESPOND TO MODULATION OF THE DOPAMINE D3 RECEPTOR
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The present invention relates to aromatic compounds of the formula (I) wherein Ar is phenyl or an aromatic 5-or 6-membered C-bound heteroaromatic radical, wherein Ar may carry 1 radical Ra and wherein Ar may also carry 1 or 2 radicals Rb; X is N or CH; E is CR6R7 or NR3;R1 is C1-C4-alkyl, C3-C4-cycloalkyl, C3-C4-cycloalkylmethyl, C3-C4-alkenyl, fluorinated Cl-C4--alkyl, fluorinated C3-C4-cycloalkyl, fluorinated C3-C 4-cycloalkylmethyl, fluorinated C3-C4--alkenyl, formyl or C1-C3-alkylcarbonyl; R1a is H, C1-C4-alkyl, C3-C4-cycloalkyl, C3-C4-cycloalkylmethyl, C3-C4-alkenyl, fluorinated C1--C4-alkyl, fluorinated C3-C4-cycloalkyl, fluorinated C 3-C4-cycloalkylmethyl, fluorinated C3--C 4-alkenyl, or R1a and R2 together are (CH 2)n with n being 2, 3 or 4, or R1a and R 2a together are (CH2)n with n being 2, 3 or 4; R2 and R2a are independently of each other H, C1-C4-alkyl or fluorinated C1-C 4-alkyl or R2a and R2 together are (CH 2)m with m being 1, 2, 3, 4 or 5; R3 is H or C1-C4-alkyl; R6, R7 independently of each other are selected from H, fluorine, C1-C4-alkyl and fluorinated C1-C4-alkyl or together form a moiety (CH2)p with p being 2, 3, 4 or 5; and the physiologically tolerated acid addition salts thereof. The invention also relates to the use of a compound of the formula (I) or a pharmaceutically acceptable salt thereof for preparing a pharmaceutical composition for the treatment of a medical disorder susceptible to treatment with a dopamine D3 receptor ligand.
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Page/Page column 88; 107-108
(2010/11/08)
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- Photochemical generation of highly destabilized vinyl cations: The effects of α- and β-trifluoromethyl versus α- and β-methyl substituents
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(Chemical Equation Presented). The photochemical reactions in methanol of the vinylic halides 1-4, halostyrenes with a methyl or a trifluoromethyl substituent at the α- or β-position, have been investigated quantitatively. Next to E/Z isomerization, the reactions are formation of vinyl radicals, leading to reductive dehalogenation products, and formation of vinyl cations, leading to elimination, nucleophilic substitution, and rearrangement products. The vinyl cations are parts of tight ion pairs with halide as the counterion. The elimination products are the result of β-proton loss from the primarily generated α-CH3 and α-CF3 vinyl cations, or from the α-CH3 vinyl cation formed from the β-CH3 vinyl cation via a 1,2-phenyl shift. The β-CF 3 vinyl cation reacts with methanol yielding nucleophilic substitution products, no migration of the phenyl ring producing the α-CF3 vinyl cation occurs. The α-CF3 vinyl cation, which is the most destabilized vinyl cation generated thus far, gives a 1,2-fluorine shift in competition with proton loss. The experimentally derived order of stabilization of the vinyl cations photogenerated in this study, α-CF3 3 3 3, is corroborated by quantum chemical calculations, provided the effect of solvent is taken into account.
- Van Alem, Kaj,Belder, Geerte,Lodder, Gerrit,Zuilhof, Han
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p. 179 - 190
(2007/10/03)
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- Highly chemoselective rhodium-catalyzed methylenation of fluorine-containing ketones.
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[reaction: see text] The rhodium(I)-catalyzed methylenation of functionalized fluorinated ketones using trimethylsilyldiazomethane proceeds to give the corresponding fluoromethylalkenes in good yields (61-90%). Remarkable chemoselectivity was observed for
- Lebel, Helene,Paquet, Valerie
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p. 1671 - 1674
(2007/10/03)
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- A novel and convenient synthetic method for producing α-(trifluoromethyl)styrenes (3)
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The Suzuki-type coupling reaction of arylboronic acids (1) with 2-bromo-3,3,3-trifluoropropene (2) in the presence of a catalytic amount of dichlorobis(triphenylphosphine)palladium {PdCl2(PPh3)2} and a base can easily give α-(trifluoromethyl)styrenes (3) in good yields. It was also found that 1,2-dibromo-3,3,3-trifluoropropane (4) underwent dehydrobromination in the presence of KOH, and subsequently, palladium-catalyzed cross-coupling with 1 to directly afford 3 in a one pot manner in excellent yields.
- Pan, Rui-Qi,Liu, Xing-Xin,Deng, Min-Zhi
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p. 167 - 170
(2007/10/03)
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- Reactivity and selectivity in the oxidation of styrene derivatives. V. studies on the oxidation of α-substituted styrenes
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The liquid phase oxidation of α-phenyl-1a, α-trimethylsilyloxy 1b, α-cyclopropyl-1c, α-trifluoromethyl-1d styrene, and styrene 1e with oxygen in chlorobenzene and cumene solution in the temperature range 55-125°C was investigated. The product yields were determined gaschromatographically. The epoxide selectivity increases up to 90°C with increasing temperature. The epoxides of 1a and 1c rearrange at higher temperatures, therefore their yield decreases. The relative chain propagation constants (kpC=C) were determined by competitive oxidations of cumene. WILEY-VCH Verlag GmbH, 1999.
- Suprun
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- Bimolecular formation of radicals by hydrogen transfer, 12: Transfer hydrogenation of p-substituted α-methylstyrenes and of 9-methylenefluorene as a criterion of mechanism
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The uncatalyzed transfer hydrogenation of substituted α-methylstyrenes with 9,10-dihydroanthracene (DHA), xanthene (XAN), or 9,10-dihydroacridine (DHAC) was studied mechanistically. The three hydrogen donors react at very similar rates and with similar activation parameters and with little discrimination between the various substituted styrenes. The kinetic isotope effects are also similar and the solvent effect is small. A hydrogen atom transfer mechanism (retrodisproportionation) is, therefore, preferred to a hydride transfer mechanism. This is supported by the very similar reactivity of the hydrogen transfer reaction of DHA and XAN with 9-methylenefluorene. The product yields in all reactions investigated in this project were >90%. VCH Verlagsgesellschaft mbH, 1997.
- Friebolin, Heike,Roers, Rolf,Ebenhoch, Jochen,Gerst, Matthias,Ruechardt, Christoph
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p. 385 - 389
(2007/10/03)
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- A short route to a Mosher's acid precursor via catalytic asymmetric dihydroxylation (AD)
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α-Methoxy-α-(trifluoromethyl)phenyl acetic acid (MTPA) is a valuable derivatizing agent for enantiomeric excess determination of alcohols and amines. A short synthesis of a precursor to this compound, based on the asymmetric dihydroxylation (AD) reaction
- Bennani,Vanhessche,Sharpless
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p. 1473 - 1476
(2007/10/02)
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- Reactivite de la trifluoro-1,1,1 propanone dans des conditions reactionelles de type Friedel-Crafts: nouvel exemple de chloroalkylation
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In the presence of one equivalent of AlCl3, the 1,1,1-trifluoro propanone 1 reacts with benzene or toluene to give 1,1,1-trifluoro-2-aryl-2-chloro propanes 4 in relatively good yield, by a new chloroalkylation reaction.This is the first example of an addition of an aromatic compound onto an aliphatic trifluoromethyl ketone.
- Bonnet-Delpon, Daniele,Charpentier-Morize, Micheline
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p. 933 - 936
(2007/10/02)
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- Carbonyl Methylenation Using a Titanium- Aluminum (Tebbe) Complex
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The titanium-aluminum (Tebbe) complex is shown to be an effective methylenating agent for a variety of carbonyl groups.The reaction is unique in that the carbonyl groups of carboxylic acid derivatives are readily methylenated.Thus vinyl enol ethers are prepared from esters and enamines are formed from amides.The complex provides a method for methylenating hindered or base sensitive ketones that is advantageous to the Wittig reagent.Selective methylenation of dicarbonyl compounds is also accomplished.
- Pine, Stanley H.,Pettit, Robert J.,Geib, Gregory D.,Cruz, Susana G.,Gallego, Claudio H.,et al.
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p. 1212 - 1216
(2007/10/02)
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- Solvolytic Reactivity of 1-Trifluoromethyl-1-phenylethyl Tosylate. Formation of a Highly Destabilized Carbonium Ion
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The solvolytic rate constants of 1-trifluoromethyl-1-phenylethyl tosylate (2) in solvents of widely different ionizing power and nucleophilicity are linearly related with slope mOTs = 1.01 to the rate of 2-adamantyl tosylate in the same solvent
- Allen, Annette D.,Jansen, Michael P.,Koshy, Kalavelil M.,Mangru, Nevindra N.,Tidwell, Thomas T.
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p. 207 - 211
(2007/10/02)
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