118917-42-3Relevant academic research and scientific papers
Enantioselective syntheses and configuration assignments of γ-chiral butenolides from Plagiomnium undulatum: Butenolide synthesis from tetronic acids
Kapferer, Tobias,Brueckner, Reinhard,Herzig, Axel,Koenig, Wilfried A.
, p. 2154 - 2162 (2005)
Both enantiomers of the γ-chiral α,β-dimethylated butyrolactones nat-1 and nat-2 from the moss Plagiomnium undulatum were synthesized stereoselectively through butenolides and tetronic acids, respectively. The configuration of the natural products was determined by GLC comparisons with mono(3-O-acetyl-6-O-tert-butyldimethylsilyl-2-O-methyl) hexakis(6-O-tert-butyldimethylsilyl-2,3-di-O-methyl)-β-cyclodextrin as a stationary phase.
Organocatalytic sequential α-aminoxylation and cis-Wittig olefination of aldehydes: Synthesis of enantiopure γ-butenolides
Devalankar, Dattatray A.,Chouthaiwale, Pandurang V.,Sudalai, Arumugam
experimental part, p. 240 - 244 (2012/06/04)
A short route to enantiopure γ-butenolides (up to 99% ee) has been developed from readily available starting materials. The strategy involves a sequential organocatalytic α-aminoxylation followed by cis-Wittig olefination of aldehydes. The utility of this protocol has been demonstrated in the asymmetric synthesis of trans-(+)-cognac lactone with high enantiomeric purity.
Organo-catalyzed enantioselective synthesis of some β-silyl γ-alkyl γ-butyrolactones as intermediates for natural products
Chowdhury, Raghunath,Ghosh, Sunil K.
experimental part, p. 1895 - 1900 (2012/01/05)
The enantioselective synthesis of some β-silyl γ-alkyl γ-butyrolactones has been achieved by an organo-catalyzed Michael addition of enolizable aldehydes onto a silylmethylene malonate followed by a silicon-facilitated Bayer-Villiger oxidation of the β-silyl aldehyde adducts as the key step. γ-Alkyl γ-butenolides were obtained from the β-silyl γ-alkyl γ-butyrolactones by Fleming-Tamao oxidation of the silyl group to a hydroxy group and subsequent elimination. These butenolides are the advanced intermediates of some natural products such as (+)-γ-caprolactone, (+)-methylenolactocine, and (-)-quercus lactone.
Enantioselective butenolide preparation for straightforward asymmetric syntheses of γ-lactones - Paraconic acids, avenaciolide, and hydroxylated eleutherol
Braukmueller, Stefan,Brueckner, Reinhard
, p. 2110 - 2118 (2007/10/03)
The naturally occurring γ-lactones (+)-methylenolactocin (13) and its enantiomer, (+)-protolichesterinic acid (14) and its enantiomer, (+)-rocellaric acid (15), and the methylene bis(γ-lactone) (-)-avenaciolide (16) were synthesized with 95-98 % ees in very few steps. Enantiocontrol was imposed by the asymmetric dihydroxylation of trans-configured β,γ-unsaturated carboxylic esters (namely compounds 1i, 1j, and 1n) with AD mix-α [for the levorotatory target structures, except for (-)-avenaciolide] or AD mix-β [for the dextrorotatory target structures plus (-)-avenaciolide]. β,γ-Unsaturated carboxylic ester 1e required increased amounts of the oxidant and auxiliary to produce the hydroxy lactone R,R-3e, a precursor of the naphtho-γ-lactone (+)-9-hydroxyeleutherol (12; 96 % ee). Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
A convergent asymmetric synthesis of γ-butenolides
Renard, Marc,Ghosez, Léon A.
, p. 2597 - 2608 (2007/10/03)
The addition of aldehydes to the new enantiomerically pure lithiated sulfoxide-orthoester 13 yielded γ-butenolides of high enantiomeric purities after elimination of phenylsulfinic acid. The cyclocondensation with ketones was less stereoselective. This new asymmetric synthesis of γ-butenolides has been applied to a convergent preparation of the antifungal antibiotic (+)-cerulenin.
Enantioselective hydrogenation of β-keto sulfones with chiral Ru(II)- catalysts: Synthesis of enantiomerically pure butenolides and γ- butyrolactones
Bertus,Phansavath,Ratovelomanana-Vidal,Genet,Touati,Homri,Hassine, B. Ben
, p. 1369 - 1380 (2007/10/03)
A series of β-hydroxy sulfones were synthesized with high enantioselectivities via a new enantioselective ruthenium-catalyzed hydrogenation using MeO-BIPHEP as a ligand. Some β-hydroxy sulfones were used in the synthesis of optically active butenolides and γ-butyrolactones with high yields and enantioselectivities over 95%.
A convergent asymmetric synthesis of γ-butenolides
Renard, Marc,Ghosez, Leon
, p. 6237 - 6240 (2007/10/03)
Addition of aldehydes to the new enantiomerically pure lithiated sulfoxide 4 yielded γ-butenolides of high enantiomeric purities after elimination of phenylsulfinic acid. The reaction with ketones was less stereoselective.
Photooxygenation of chiral dienol ethers: Asymmetric synthesis of alkoxydioxines
Dussault, Patrick H.,Han, Qiang,Sloss, Darby G.,Symonsbergen, David J.
, p. 11437 - 11454 (2007/10/03)
The addition of 1O2 to chiral dienol ethers provides a new route to alkoxydioxines (alkoxyendoperoxides). Depending upon substitution and geometry, the [4+2] cycloaddition is accompanied or even supplanted by [2+2] cycloaddition leading to alkene cleavage and/or ene-like reaction leading to allylic hydroperoxides. The diastereoselectivity of cycloaddition is ultimately limited by the conformational freedom of the dienol ether substrates.
Synthetic Routes to Allenic Acids and Esters and Their Stereospecific Conversion to Butenolides
Marshall, James A.,Wolf, Mark A.,Wallace, Eli M.
, p. 367 - 371 (2007/10/03)
The synthesis of allenic acids and esters and their conversion to butenolides has been examined in some detail. Racemic butenolides 10 are efficiently prepared from the esters 8 through treatment with BCl3 and exposure of the derived acid 9 to catalytic AgNO3 in acetone. Conversion of the enantioenriched allenylstannane (S)-17 to the acid 18 through lithiation and subsequent carboxylation with CO2 afforded racemic product. The enantioenriched propargylic mesylates 16 and 22 afforded the allenic esters 19 and 23 with inversion of configuration through treatment with Pd(Ph3P)4, CO, and the appropriate alcohol in THF. These reactions proceeded with ca. 10% or less of racemization. The allenic esters 23 yielded the iodobutenolides 24 by reaction with IBr. Hydrogenolysis to the butenolide 25 was achieved with Pd(PPh3)4 and Bu3SnH. Alternatively, the allenic acids 27 could be prepared directly from mesylates 22 with Pd(PPh3)4 and CO in aqueous THF. Cyclization to the butenolides 25 was achieved, as before, with catalytic AgNO3.
Concise syntheses of natural γ-butyrolactones, (+)-trans-whisky lactone, (+)-trans-cognac lactone, (-)-methylenolactocin, (+)-nephrosteranic acid, and (+)-roccellaric acid using novel chiral butenolide synthons
Takahata,Uchida,Momose
, p. 5628 - 5633 (2007/10/03)
cis-4-Hydroxy-5-(iodomethyl)-4,5-dihydro-2(3H)-furanones (1 and ent-1) were converted by cross-coupling with several Grignard-derived cuprates followed by benzoylation and base-induced elimination into new chiral butenolides 12, 14, ent-14, 20, and 27. The sequential conjugate addition - quenching of these butenolides under complete stereocontrol provided several polysubstituted γ-butyrolactones including flavor components [(±)-trans-whisky lactone (3) and (+)-trans-cognac lactone (4)], the antitumor antibiotic lactone (-)-methylenolactocin (5), and lichen components [(+)-nephrosteranic acid (7) and (+)-roccellaric acid (8)].
