83706-94-9Relevant academic research and scientific papers
Dramatic Effect of γ-Heteroatom Dienolate Substituents on Counterion Assisted Asymmetric Anionic Amino-Cope Reaction Cascades
Das, Pradipta,Delost, Michael D.,Qureshi, Munaum H.,Bao, Jianhua,Fell, Jason S.,Houk, Kendall N.,Njardarson, Jon T.
supporting information, p. 5793 - 5804 (2021/05/07)
We report a dramatic effect on product outcomes of the lithium ion enabled amino-Cope-like anionic asymmetric cascade when different γ-dienolate heteroatom substituents are employed. For dienolates with azide, thiomethyl, and trifluoromethylthiol substituents, a Mannich/amino-Cope/cyclization cascade ensues to form chiral cyclohexenone products with two new stereocenters in an anti-relationship. For fluoride-substituted nucleophiles, a Mannich/amino-Cope cascade proceeds to afford chiral acyclic products with two new stereocenters in a syn-relationship. Bromide- and chloride-substituted nucleophiles appear to proceed via the same pathway as the fluoride albeit with the added twist of a 3-exo-trig cyclization to yield chiral cyclopropane products with three stereocenters. When this same class of nucleophiles is substituted with a γ-nitro group, the Mannich-initiated cascade is now diverted to a β-lactam product instead of the amino-Cope pathway. These anionic asymmetric cascades are solvent- and counterion-dependent, with a lithium counterion being essential in combination with etheral solvents such as MTBE and CPME. By altering the geometry of the imine double bond from E to Z, the configurations at the R1 and X stereocenters are flipped. Mechanistic, computational, substituent, and counterion studies suggest that these cascades proceed via a common Mannich-product intermediate, which then proceeds via either a chair (X = N3, SMe, or SCF3) or boat-like (X = F, Cl, or Br) transition state to afford amino-Cope-like products or β-lactam in the case of X = NO2.
Cobalt-Catalyzed Diastereo- And Enantioselective Reductive Allyl Additions to Aldehydes with Allylic Alcohol Derivatives via Allyl Radical Intermediates
Wang, Lei,Wang, Lifan,Li, Mingxia,Chong, Qinglei,Meng, Fanke
supporting information, p. 12755 - 12765 (2021/08/30)
Catalytic generation of ambiphilic π-allyl-metal complexes and their utility in enantioselective transformations constitutes a powerful approach for introduction of allyl groups to a molecule. Herein an unprecedented cobalt-catalyzed highly site-, diastereo-, and enantioselective protocol for stereoselective formation of nucleophilic allyl-Co(II) complexes followed by addition to aldehydes is presented. The reaction features diastereo- and enantioconvergent conversion of easily accessible allylic alcohol derivatives to diversified enantioenriched homoallylic alcohols with a remarkably broad scope of allyl groups that can be introduced. Mechanistic studies indicated that allyl radical intermediates were involved in this process. These new discoveries establish a new strategy for development of enantioselective transformations through capture of radicals by chiral Co complexes, pushing forward the frontier of Co complexes for enantioselective catalysis.
PROCESS FOR PREPARATION OF 4,4,4- TRIFLUOROBUT-2-EN-1-OL AND INTERMEDIATE THEREOF
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Page/Page column 12, (2020/07/31)
The present invention provides a process for preparation of 4,4,4- trifluorobut-2-en-1-ol from alkyl 4,4,4-trifluorobut-2-enoate and also provides one step process for preparation of alkyl 4,4,4-trifluorobut-2-enoate from corresponding hydroxy derivative using mild and easily available reagents.
Copper-Catalyzed Asymmetric Defluoroborylation of 1-(Trifluoromethyl)Alkenes
Gao, Pan,Yuan, Chengkai,Zhao, Yue,Shi, Zhuangzhi
supporting information, p. 2201 - 2211 (2018/10/02)
gem-Difluoroalkenes have steric and electronic profiles similar to those of ketones, aldehydes, and esters, and consequently have been used widely as carbonyl isosteres in modern drug discovery. Although many attempts have been made to achieve gem-difluor
A Copper(I)-Catalyzed Enantioselective γ-Boryl Substitution of Trifluoromethyl-Substituted Alkenes: Synthesis of Enantioenriched γ,γ-gem-Difluoroallylboronates
Kojima, Ryoto,Akiyama, Sota,Ito, Hajime
supporting information, p. 7196 - 7199 (2018/06/15)
The first catalytic enantioselective γ-boryl substitution of CF3-substituted alkenes is reported. A series of CF3-substituted alkenes was treated with a diboron reagent in the presence of a copper(I)/Josiphos catalyst to afford the c
Introduction of the 4,4,4-Trifluorobut-2-ene Chain Exploiting a Regioselective Tsuji-Trost Reaction Catalyzed by Palladium Nanoparticles
Hemelaere, Rémy,Desroches, Justine,Paquin, Jean-Fran?ois
supporting information, p. 1770 - 1773 (2015/04/14)
A palladium-nanoparticle-catalyzed Tsuji-Trost reaction of 4,4,4-trifluorobut-2-en-1-yl acetate and ethyl(4,4,4-trifluorobut-2-en-1-yl)carbonate was accomplished with various nucleophiles including phenols, amines, and malonates. In the case of the phenols, isomerization of the double bond in the product (up to 20%) was observed as a side reaction. Further synthetic transformations including hydrogenation, the Diels-Alder reaction, and asymmetric dihydroxylation of a product were also examined.
Systematic study of the reactivity of (E)-4,4,4-trifluorobut-2-en-1-yl 4-methylbenzenesulfonate towards different classes of nucleophiles
Forcellini, Elsa,Hemelaere, Rémy,Desroches, Justine,Paquin, Jean-Fran?ois
, p. 216 - 221 (2015/11/02)
A systematic study of the reactivity of (E)-4,4,4-trifluorobut-2-en-1-yl 4-methylbenzenesulfonate towards different classes of nucleophiles (alcohols, amines, thiols and malonates) was performed. A single set of reaction conditions (with small variations) allowed the isolation of the substitution product in moderate to good yields for all the nucleophiles tested with the exception of benzyl alcohol and indole.
Practical synthesis of 4,4,4-trifluorocrotonaldehyde: A versatile precursor for the enantioselective formation of trifluoromethylated stereogenic centers via organocatalytic 1,4-additions
Shibatomi, Kazutaka,Narayama, Akira,Abe, Yoshiyuki,Iwasa, Seiji
experimental part, p. 7380 - 7382 (2012/10/08)
The practical synthesis of 4,4,4-trifluorocrotonaldehyde (1) and its application to enantioselective 1,4-additions are described. The organocatalytic 1,4-addition of 1 with several nucleophiles such as heteroaromatics, alkylthiols and aldoximes afforded t
Synthesis and cytotoxic activity of fluorinated analogues of Goniothalamus lactones. Impact of fluorine on oxidative processes
Dumitrescu, Lidia,Huong, Doan Thi Mai,Hung, Nguyen Van,Crousse, Benoit,Bonnet-Delpon, Danièle
experimental part, p. 3213 - 3218 (2010/08/20)
Novel fluorinated analogues of goniothalamin 1 and howiinol A 2 have been prepared from trifluorocrotonate derivatives. Trifluoromethyl goniothalamin (R/S) 4 showed a slightly lower activity than 1, while the trifluoromethyl howiinol A 16 exhibited similar activities on several cell lines in the micromolar range. Unlike (R) goniothalamin and howiinol A, trifluoromethyl parent compounds remained unchanged when submitted to biomimetic oxidative systems.
4-SUBSTITUTED PYRR0LIDIN-2-0NES AND THEIR USE
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Page/Page column 24, (2010/11/26)
The present invention relates to optically enriched or substantially optically pure 4-substituted-pyrrolidin-2-ones of formula (III), and their uses for the synthesis of 2-oxo-pyrrolidin-l-yl derivatives.
