- Highly enantioselective construction of CF3-bearing all-carbon quaternary stereocenters: Hiral spiro-fused bisoxazoline ligands with 1,1′-binaphthyl sidearm for asymmetric Michael-type Friedel-Crafts reaction
-
A novel class of chiral spiro-fused bisoxazoline ligands possessing a deep chiral pocket was prepared. The developed ligands have been employed in the nickel-catalyzed highly enantioselective Michael-type Friedel-Crafts reaction, affording the products bearing a trifluoromethylated all-carbon quaternary stereocenter with moderate to excellent yields (up to 99%) and good to excellent enantioselectivies (up to > 99.9% ee). Moreover, a proposed model of chiral pocket revealed that the attack of indole from the Re-face of β-CF3-β-disubstituted nitroalkene was favorable.
- Bao, Robert Li-Yuan,Fu, Kang,Shi, Lei
-
supporting information
(2021/11/27)
-
- REACTIVE EXTRACTION OF WATER
-
Described herein are methods and compounds for extracting water from an aqueous solution. For example, some embodiments include method for extracting water from an aqueous solution, comprising contacting the aqueous solution with a compound comprising one or more carbonyl moieties having an equilibrium constant for a hydration of the carbonyl moiety of at least about 0.5; separating a composition comprising the hydrated compound from the aqueous solution; and reacting the hydrated compound to obtain water.
- -
-
Paragraph 0073-0076
(2020/04/09)
-
- Visible light-promoted umpolung coupling of aryl tri-/difluoroethanones with 2-alkenylpyridines
-
Tertiary alcohols bearing a trifluoromethyl group are of considerable medicinal interest. Using an umpolung strategy, we herein report the first intermolecular reductive cross-coupling of aryl tri-/difluoroethanones with 2-alkenylpyridines with the aid of a Br?nsted acid catalyst upon visible-light irradiation. This metal-free reaction is operationally simple and performed at ambient temperature, allowing access to desired tertiary alcohols with tri-/difluoromethyl groups in moderate to excellent yields. The commercially available and easily handled Hantzsch ester effectively serves as an electron donor, as well as a hydrogen atom source.
- Xu, Xiao,Min, Qing-Qiang,Li, Na,Liu, Feng
-
supporting information
p. 11017 - 11020
(2018/10/08)
-
- Domino C-F Bond Activation of the CF3 Group: Synthesis of Fluorinated Dibenzo[a,c][7]annulenes from 2-(Trifluoromethyl)-1-alkenes and 2,2′-Diceriobiaryls
-
The construction of ring-fluorinated seven-membered carbocycles was readily achieved via the domino SN2′-type/SNV reaction between 2-(trifluoromethyl)-1-alkenes and 1,4-carbodianions. The SN2′-type reaction of 2-(trifluoromethyl)-1-alkenes with 2,2′-diceriobiaryls generated the intermediary 1,1-difluoro-1-alkenes bearing a monoceriobiaryl moiety, which in turn underwent intramolecular SNV reaction to afford fluorinated 5H-dibenzo[a,c][7]annulenes.
- Fujita, Takeshi,Takazawa, Marina,Sugiyama, Kazuki,Suzuki, Naoto,Ichikawa, Junji
-
supporting information
p. 588 - 591
(2017/02/10)
-
- Copper-Mediated Trifluoroacetylation of Arenediazonium Salts with Ethyl Trifluoropyruvate
-
A copper-mediated trifluoroacetylation of various arenediazonium salts with ethyl trifluoropyruvate is reported. The reaction proceeded smoothly under mild conditions at room temperature giving trifluoromethyl aryl ketones in moderate to good yields. A variety of functional groups, including methoxy, hydroxy, ester, ketone, trifluoromethyl, and halide groups, were well tolerated. A possible reaction mechanism involving an aryl radical intermediate was proposed and supported by experimental evidence. This reaction provides a new route to trifluoromethyl aryl ketones, notable synthetic targets, from the corresponding anilines.
- Wu, Wei,Tian, Qinli,Chen, Taotao,Weng, Zhiqiang
-
supporting information
p. 16455 - 16458
(2016/11/11)
-
- Asymmetric Construction of Pyrrolidines Bearing a Trifluoromethylated Quaternary Stereogenic Center via CuI-Catalyzed 1,3-Dipolar Cycloaddition of Azomethine Ylides with β-CF3-β,β-Disubstituted Nitroalkenes
-
A direct and convenient method has been developed for the synthesis of optically active pyrrolidines bearing a quaternary stereogenic center containing a CF3 group at the C-3 position of the pyrrolidine ring. The synthesis system, CuI/Si-FOXAP-catalyzed exo-selective 1,3-dipolar cycloaddition of azomethine ylides with β-CF3-β,β-disubstituted nitroalkenes, provides pyrrolidines with high diastereoselectivities (up to >98:2 d.r.) and excellent enantioselectivities (up to >99.9 ee) and performs well for a broad scope of substrates under mild conditions.
- Tang, Li-Wei,Zhao, Bao-Jing,Dai, Li,Zhang, Man,Zhou, Zhi-Ming
-
supporting information
p. 2470 - 2477
(2016/09/13)
-
- PROCESS FOR THE PREPARATION OF HALO-SUBSTITUTED TRIFLUOROACETOPHENONES
-
The invention relates to a process for the preparation of a compound of formula I (I), wherein R1 is hydrogen, fluoro or chloro; which process comprises a) reacting a compound of formula II (II), wherein R1 is hydrogen, fluoro or chloro; with a nitration agent to the compound of formula (III), wherein R1 is hydrogen, fluoro or chloro; and b) reacting the compound of formula III with chlorine gas at temperature from 180°C to 250°C to the compound of formula I.
- -
-
Page/Page column 5; 6
(2016/05/24)
-
- PROCESS FOR THE PREPARATION OF HALO-SUBSTITUTED BENZENES
-
The present invention relates to a process for the preparation of a compound of formula (I), wherein R1 is hydrogen, fluoro or chloro; which process comprises a) reacting a compound of formula (II), wherein R1 is hydrogen, fluoro or chloro; with a nitration agent to the compound of formula (III), wherein R1 is hydrogen, fluoro or chloro; b) reacting the compound of formula III with a chlorinating agent to the compound of formula (IV), wherein R1 is hydrogen, fluoro or chloro; and c) reacting the compound of formula (III) with chlorine gas at a temperature from 180°C to 250°C to the compound of formula (I).
- -
-
Page/Page column 8
(2016/12/26)
-
- Palladium-catalyzed carbonylative coupling of aryl iodides with an organocopper reagent: A straightforward procedure for the synthesis of aryl trifluoromethyl ketones
-
A palladium-catalyzed carbonylative coupling of aryl iodides with a (trifluoromethyl)copper reagent has been developed. A wide range of substrates have been transformed into their corresponding trifluoromethyl ketones in good to excellent yields under mild conditions with high efficiency and excellent functional-group compatibility. Preliminary mechanistic investigations suggest that the transmetallation of an acylpalladium intermediate with the (trifluoromethyl)copper reagent seems to be involved in the catalytic cycle. Notably, this report represents one of the few studies on carbonylative coupling with organocopper reagents.
- Zhu, Fengxiang,Yang, Guangfu,Zhou, Shaolin,Wu, Xiao-Feng
-
p. 57070 - 57074
(2016/07/07)
-
- In Situ Proteome Profiling and Bioimaging Applications of Small-Molecule Affinity-Based Probes Derived from DOT1L Inhibitors
-
DOT1L is the sole protein methyltransferase that methylates histone H3 on lysine 79 (H3K79), and is a promising drug target against cancers. Small-molecule inhibitors of DOT1L such as FED1 are potential anti-cancer agents and useful tools to investigate the biological roles of DOT1L in human diseases. FED1 showed excellent in vitro inhibitory activity against DOT1L, but its cellular effect was relatively poor. In this study, we designed and synthesized photo-reactive and "clickable" affinity-based probes (AfBPs), P1 and P2, which were cell-permeable and structural mimics of FED1. The binding and inhibitory effects of these two probes against DOT1L protein were extensively investigated in vitro and in live mammalian cells (in situ). The cellular uptake and sub-cellular localization properties of the probes were subsequently studied in live-cell imaging experiments, and our results revealed that, whereas both P1 and P2 readily entered mammalian cells, most of them were not able to reach the cell nucleus where functional DOT1L resides. This offers a plausible explanation for the poor cellular activity of FED1. Finally with P1/P2, large-scale cell-based proteome profiling, followed by quantitative LC-MS/MS, was carried out to identify potential cellular off-targets of FED1. Amongst the more than 100 candidate off-targets identified, NOP2 (a putative ribosomal RNA methyltransferase) was further confirmed to be likely a genuine off-target of FED1 by preliminary validation experiments including pull-down/Western blotting (PD/WB) and cellular thermal shift assay (CETSA). Minimalist "clickable" probes: Small-molecule probes P1 and P2 based on FED1 (a known DOT1L inhibitor) were developed and successfully used in experiments including live-cell imaging, in situ proteome profiling, and off-target identification (see scheme).
- Zhu, Biwei,Zhang, Hailong,Pan, Sijun,Wang, Chenyu,Ge, Jingyan,Lee, Jun-Seok,Yao, Shao Q.
-
supporting information
p. 7824 - 7836
(2016/06/09)
-
- Catalytic asymmetric hydrogenation of α-CF3- or β-CF3-Substituted acrylic acids using Rhodium(I) complexes with a combination of chiral and achiral ligands
-
Only the mixture works! Acrylic acid derivatives with CF3 substituents in α or β position were efficiently hydrogenated in the presence of a RhI complex with a chiral secondary phosphine oxide (SPO; see scheme) and an achiral Ph3P as ligands. The corresponding propanoic acid derivatives were obtained with generally high conversion (>99 %) and high enantioselectivity (92->99 %). Copyright
- Dong, Kaiwu,Li, Yang,Wang, Zheng,Ding, Kuiling
-
supporting information
p. 14191 - 14195
(2014/01/06)
-
- Cross-linked dendrimer hosts containing reporter groups for amine guests
-
The integration of a chromogenic reporter group into the recently reported (Zimmerman, S. C.; Wendland, M. S.; Rakow, N. A.; Zharov, I.; Suslick, K. S. Nature 2002, 418, 399-403) monomolecular imprinting approach is described. The resulting highly cross-linked, macromolecular hosts show rapid, selective, high affinity, two-point binding of straight-chain diamine guests. Over longer times, the hosts are more promiscuous, binding a broader range of diamines. A rigorous test of imprinting was performed wherein the cross-reactivities of two dendrimers derived from different templates are compared. The test reveals a guest-dependent kinetic binding effect masquerading as evidence of a highly selective two-point imprinting process. Copyright
- Mertz, Eric,Zimmerman, Steven C.
-
p. 3424 - 3425
(2007/10/03)
-
- A simple method for the preparation of aryl trifluoromethyl ketones
-
4-Dimethylamino-1-trifluoroacetylpyridinium trifluoroacetate (2) is an effective, easy to handle and stable trifluoroacetylation agent. Aryl trifluormethyl ketones 4 are obtained in good yields by reaction of 2 with aromatic compounds 3 in the presence of aluminum chloride.
- Simchen, Gerhard,Schmidt, Andreas
-
p. 1093 - 1094
(2007/10/03)
-
- Perfluoroalkylations and perfluorooxaalkylations. Part 2. Copper-mediated cross-coupling of secondary perfluorooxaalkyl iodides and aryl halides
-
The first successful application of the copper-mediated cross-coupling reaction using secondary perfluorooxaalkyl iodides and iodoaromatic substrates is described.The yields of the cross-coupled products are optimized by careful choice and control of the experimental conditions.The by-products formed are identified and their probable mode of formation is discussed.
- Chen, Grace J.,Chen, Loomis S.,Eapen, Kalathil C.
-
-
- Extent of Charge Transfer in the Photoreduction of Phenyl Ketones by Alkylbenzenes
-
Rate constants for triplet-state reaction of various ring-substituted benzophenones (BPs), acetophenones (APs), and α,α,α-trifluoroacetophenones (TFAs) with toluene and p-xylene have been determined by a combination of flash kinetics, steady-state quenching, and quantum yield measurements.The relative amounts of primary and tertiary radicals formed by reaction of the same ketons with p-cymene have also been measured.For all three types of ketones, rate constants correlate well with triplet ketone reduction potentials.The magnitude of the kinetic isotope effects observed with toluene-d8 and p-xylene-d10 diminishes as the ketones become easier to reduce.All of the ketone triplets react with alkylbenzenes primarily by a charge-transfer mechanism, with the rate-determining step changing from complexation to hydrogen transfer as the ketones become harder to reduce.The least reactive AP triplets probably react significantly via simple hydrogen atom abstraction as well.Those ketones with n,?* lowest triplets (all BPs and some APs) react with p-cymene to give primary/tertiary radical ratios that vary no more than a factor of 2 from the 0.40 value displayed by tert-butoxy radicals; those with ?,?* lowest triplets (TFAs and some APs) give ratios that favor primary radicals and that vary by an order of magnitude with the triplet ketone reduction potential.The variation in cymene product ratios reflect different orientations for attack on cymene by n,?* and ?,?* triplets and differing degrees of partial electron transfer within the exciplexes, which are not tight radical ion pairs.The variation seen for ?,?* triplets represents a stereoelectronic effect within face-to-face exciples, as evidenced by the excerptional behavior of p-diacylbenzenes, which give the highest ratio of tertiary radicals from cymene.There is no set intrinsic ratio of reactivity for ?,?* triplets vs. n,?* triplets in these CT reactions.The two types of triplets show similar reactivity for the more easily reduced triplets, with the harder to reduce ?,?* triplets being only one-tenth as reactive as n,?* triplets of comparable triplet reduction potential.When the extent of electron transfer in the exciplex is small, hydogen transfer is rate determining and ?,?* reactivity drops.A study of two radical reactions which generate benzyl and α-hydroxy-α-methylbenzyl radicals indicates that radical disproportionation cannot explain the low quantum yields (0.10) of most ketone-toluene photoreductions, which apparently involve substantial radiation less decay by the exciplex intermediates.
- Wagner, Peter J.,Truman, Royal J.,Puchalski, Alan E.,Wake, Ronald
-
p. 7727 - 7738
(2007/10/02)
-
- MECHANISMS OF FREE-RADICAL REACTIONS. XIII. MECHANISM AND SELECTIVITY OF THE FREE-RADICAL HALOGENATION OF ALKYL AROMATIC HYDROCARBONS WITH FLUOROALKYL SUBSTITUENTS
-
The free-radical chlorination and bromination of 1-fluoro-2-arylethanes and 1,1,1-trifluoro-2-arylethanes was studied by the method of competing reactions.In all cases a good correalation between log krel and the Brown ?+ constants was observed.The variation of the selectivity in the transition from one reaction series to the other indicates that two independent factors which determine the reactivity (the change in the dissociation energy of the C-H bond and the polar effect of the substituents) have a simultaneous effect.
- Dneprovskii, A. S.,Eliseenkov, E. V.,Mil'tsov, S. A.
-
p. 317 - 324
(2007/10/02)
-
- Derivatives of arylalkanoic acids, compositions and use
-
There are now described some novel alpha-[1-aryl-2,2,2-trifluoroethoxy (or-ethylthio)]alkanoic acids that are useful for reducing triglycerides and cholesterol levels in the blood of animals. The percentage reduction in test rats has been observed to be from 20 to 65 for triglycerides and from 15 to 50 for cholesterol. A representative compound of the invention is alpha-(2,2,2-trifluoro-1-phenyl-1-ethoxy)butyric acid. Most of the compounds have an LD50 greater than 800 mg/kg, intraperitoneally, in male mice. A method of use, compositions, and a process for synthesis are also described.
- -
-
-
