20215-56-9Relevant academic research and scientific papers
Stereoselective amine addition to six-membered cyclic nitronates promoted by silyl triflate
Mikhaylov, Andrey A.,Dilman, Alexander D.,Khomutova, Yulia A.,Arkhipov, Dmitry E.,Korlyukov, Alexander A.,Ioffe, Sema L.
, p. 5670 - 5677 (2013)
Six-membered cyclic nitronates couple with amines or their N-silyl derivatives in a diastereoselective fashion to give 3-amino-substituted nitroso acetals in 53-89 % yield through silyl triflate electrophilic catalysis. Stereodifferentiation of this process is determined by thermodynamic control, which is realized due to reversibility of amine addition and a decreased nitrogen inversion barrier in the resulting nitroso acetals. Selected chemical transformations of nitroso acetals were examined. N-Silylamines add to six-membered nitronates with high diastereoselectivity. The reaction follows an original mechanism in which thermodynamic control plays the key role. Copyright
Reactions of β-Lactones with Lewis Acids: Ring Enlargement Versus β-Elimination
Mulzer, Johann,Pointner, Andreas,Strasser, Rupert,Hoyer, Karsten
, p. 3679 - 3682 (1995)
On treatment with MgBr2 the β-spirolactones 7 and 10 undergo ring enlargement to the γ-lactones 8 and 11, whereas the β-spirolactones 13 show diastereoselective β-elimination to form the β,γ-unsaturated acids 14.The lewis acid influence on the migratory aptitude of Me versus H is studied for β-lactone 18.
Blue light-promoted photolysis of aryldiazoacetates
Jurberg, Igor D.,Davies, Huw M. L.
, p. 5112 - 5118 (2018/06/12)
Aryldiazoacetates can undergo photolysis under blue light irradiation (460-490 nm) at room temperature and under air in the presence of numerous trapping agents, such as styrene, carboxylic acids, amines, alkanes and arenes, thus providing a straighforward and general platform for their mild functionalization.
Access to Polycyclic Derivatives by Triflate-Catalyzed Intramolecular Hydroarylation
Cacciuttolo, Bastien,Poulain-Martini, Sophie,Fontaine-Vive, Fabien,Abdo, Mahmoud Ali Hussein,El-Kashef, Hussein,Du?ach, Elisabet
supporting information, p. 7458 - 7468 (2016/02/18)
An efficient and versatile synthesis of indane, tetralin and benzosuberan derivatives has been developed; the synthesis starts from nonactivated aromatic compounds bearing unsaturated side chains and is a bismuth(III) or indium(III) trifluoromethanesulfonate-catalysed atom-economic process. A variety of polycyclic compounds have been isolated in high yields. Lactonisation could be observed for esters with 2,2-disubstituted terminal olefins through a Lewis acid catalysed reaction between the olefin and one of the ester groups.
Kinetic resolution of racemic carboxylic acids through asymmetric protolactonization promoted by chiral phosphonous acid diester
Sakuma, Masayuki,Sakakura, Akira,Ishihara, Kazuaki
supporting information, p. 2838 - 2841 (2013/07/19)
Chiral phosphonium salts induce the kinetic resolution of racemic α-substituted unsaturated carboxylic acids through asymmetric protolactonization. Both the lactones and the recovered carboxylic acids are obtained with high enantioselectivities and high S
Isothiourea-catalysed asymmetric C-acylation of silyl ketene acetals
Woods, Philip A.,Morrill, Louis C.,Bragg, Ryan A.,Smith, Andrew D.
body text, p. 11060 - 11067 (2011/10/19)
Screening of a range of chiral isothioureas and acyl donors to promote the asymmetric C-acylation of silyl ketene acetals indicates that C(2)-aryl-dihydropyrimidobenzothiazole-derived isothioureas and propionic anhydride give optimal reactivity and enantioselectivity in this process. Under optimised conditions 3-acyl-3-aryl or 3-acyl-3-alkylfuranones are prepared in good yields and moderate to excellent enantioselectivities (up to 98 % ee; ee=enantiomeric excess).
Carbon-carbon bond-forming reactions of α-carbonyl carbocations: Exploration of a reversed-polarity equivalent of enolate chemistry
Lai, Ping-Shan,Dubland, Joshua A.,Sarwar, Mohammed G.,Chudzinski, Michael G.,Taylor, Mark S.
supporting information; experimental part, p. 7586 - 7592 (2011/10/12)
Carbon-carbon bond-forming reactions of putative α-carbonyl carbocation intermediates generated by Lewis acid- or silver-promoted ionizations of toluenesulfonate or halide leaving groups are described. This under-exploited mode of reactivity represents an 'umpolung' of conventional enolate chemistry, and enables C-C bond construction in both intra- and intermolecular contexts. Attempts to develop diastereoselective variants of this process using chiral ester and oxazolidinone-based auxiliaries are discussed.
Isothiourea-mediated stereoselective C-acylation of silyl ketene acetals
Woods, Philip A.,Morrill, Louis C.,Lebl, Tomas,Slawin, Alexandra M. Z.,Bragg, Ryan A.,Smith, Andrew D.
supporting information; experimental part, p. 2660 - 2663 (2010/08/21)
Isothiourea DHPB promotes the diastereoselective C-acylation of silyl ketene acetals with anhydrides or benzoyl fluoride, giving 3-acyl-3-aryl or 3-acyl-3-alkylfuranones in excellent yields and stereoselectivities (up to 99:1 dr).
Catalytic enantioselective synthesis of quaternary stereocenters via intermolecular C-acylation of silyl ketene acetals: Dual activation of the electrophile and the nucleophile
Mermerian, Ara H.,Fu, Gregory C.
, p. 4050 - 4051 (2007/10/03)
A nucleophile-catalyzed asymmetric intermolecular C-acylation of silyl ketene acetals by anhydrides has been developed, furnishing quaternary stereocenters with high enantioselectivity. Mechanistic studies support the hypothesis that the reaction involves activation both of the silyl ketene acetal (generation of an enolate) and of the anhydride (formation of an acylpyridinium ion). Copyright
Indane derivative and perfumery composition comprising the same
-
, (2008/06/13)
Indane derivatives useful as fragrance-imparting components are disclosed. The represented indane derivatives by the formula (I), STR1 wherein ring A is a benzene or cyclohexane ring and R1 is a hydrogen atom, an alkyl group having 1-4 carbon a
