- A general and concise stereodivergent chiral pool approach toward trans-(4S,5R)- and cis-(4R,5R)-5-alkyl-4-methyl-γ-butyrolactones: Syntheses of (+)-trans- and (+)-cis-whisky and cognac lactones from D-(+)-mannitol
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A straightforward synthesis of (+)-trans-(4S,5R)- and (+)-cis-(4R,5R)-whisky lactones starting from D-(+)-mannitol has been reported here in fewer number of efficient steps compared to existing literature processes involving D-mannitol as the chiral pool starting material. Chiron approach directly translated chirality of D-mannitol to one of the two chiral centers in these target molecules. Toward this end, stereoisomerically pure trans- and cis-iodomethyl-γ-lactones were formed in the penultimate step. These two acted as versatile advanced common intermediates as they were also converted to the (+)-trans-(4S,5R)- and (+)-cis-(4R,5R)-cognac lactones, respectively. To the best of our knowledge, till date no synthesis of cognac lactones starting from D-mannitol has been reported. All these lactones are identified as the key aroma components of aged alcoholic beverages.
- Manna, Avrajit,Chakraborty, Ipsita,Chatterjee, Sandip,Bhaumik, Tanurima
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- Asymmetric synthesis of: Trans -4,5-disubstituted γ-butyrolactones involving a key allylboration step. First access to (-)-nicotlactone B and (-)-galbacin
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An efficient asymmetric synthesis of trans-4,5-disubstituted γ-butyrolactones from aldehydes and enantioenriched γ-carbamate alkenylboronates is reported. The cornerstone of this strategy is the implementation of sequential [3,3]-allyl cyanate rearrangement/allylboration/nucleophilic addition/cyclisation reactions. Diverse γ-butyrolactones such as the flavouring compounds, (+)-trans-whiskey lactone and (+)-trans-cognac lactone, as well as an advanced intermediate towards the first synthesis of natural products, (-)-nicotlactone B and (-)-galbacin, have thus been obtained.
- Henrion,Macé,Vallejos,Roisnel,Carboni,Villalgordo,Carreaux
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p. 1672 - 1678
(2018/03/21)
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- Enantioselective, Catalytic One-Pot Synthesis of γ-Butyrolactone-Based Fragrances
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Herein the preparative (1 g scale), stereoselective syntheses of various alkyl-substituted γ-butyrolactone fragrances 1 is described. The α,β-unsaturated γ-keto esters 2 as starting materials were synthesized by a Horner-Wadsworth-Emmons reaction and are further reduced by an ene reductase and alcohol dehydrogenase in a one-pot enzyme cascade to nine desired γ-butyrolactones 1, among them whisky (1 c) and cognac lactone (1 d). The products 1 were obtained in moderate to good yields and very good diastereoselectivities. Furthermore, the position of a nBu-substituent was permutated to study the effect on the enzyme cascade.
- Kumru, Ceyda,Classen, Thomas,Pietruszka, J?rg
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p. 4931 - 4940
(2018/10/15)
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- Organocatalytic sequential α-aminoxylation and cis-Wittig olefination of aldehydes: Synthesis of enantiopure γ-butenolides
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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.
- Devalankar, Dattatray A.,Chouthaiwale, Pandurang V.,Sudalai, Arumugam
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experimental part
p. 240 - 244
(2012/06/04)
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- Radical cyclization route to the stereoselective synthesis of ( )-trans-cognac lactone and ( )-trans-aerangis lactone
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Stereoselective total synthesis of two chiral lactones, (+)-trans-cognac lactone (1b) and (+)-trans-aerangis lactone (2c), has been achieved from the same intermediate using a radical-based cyclization route. Copyright Taylor & Francis Group, LLC.
- Sabitha, Gowravaram,Bhikshapathi,Yadav
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p. 561 - 569
(2007/10/03)
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- Atom transfer radical cyclization (ATRC) applied to a chemoenzymatic synthesis of Quercus lactones
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The natural fragrances (+)-trans whisky lactone 2 and (+)-trans cognac lactone 4, together with a minor amount of their (-)-cis stereoisomers, were prepared in 50% and 42% overall yield, respectively, starting from racemic 1-hepten-3-ol (±)-5 and 1-octen-3-ol (±)-6. The procedure involved first the enantioconvergent, lipase mediated transformation of the secondary allylic alcohols derived dichloroacetates (±)-7 and (±)-8 into the corresponding homochiral (+)-7 and (+)-8, combined with their cyclization under a transition metal catalyzed atom transfer process.
- Felluga, Fulvia,Forzato, Cristina,Ghelfi, Franco,Nitti, Patrizia,Pitacco, Giuliana,Pagnoni, Ugo Maria,Roncaglia, Fabrizio
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p. 527 - 536
(2007/10/03)
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- Stereoselective synthesis of (+)-nephrosteranic acid, (+)-trans-cognac lactone, and (+)-trans-whisky lactone using a chiral cyclohexadienyl Ti compound
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We present the stereoselective transfer of cyclohexadienyl from 3-metalated 1,4-cyclohexadienes to various aldehydes. Lewis-acid-mediated "allylation" of aldehydes by treatment with 3-silylated and 3-stannylated 1,4-cyclohexadienes could not be achieved with high diastereoselectivity. In contrast, cyclohexadienyl titanium compounds reacted with both aliphatic and aromatic aldehydes with good-to-excellent diastereoselectivities. Reaction of a chiral TADDOL-derived (TADDOL, 2,2-dimethyl-α,α,α′,α′-tetraphenyl-1, 3-dioxolandimethanol) cyclohexadienyl Ti derivative with various aldehydes led to the corresponding homoallylic alcohols with excellent diastereo- and enantioselectivities. Lower selectivities were obtained with chiral β-cyclohexadienyldiisopinocampheylborane. The 1,3-cyclohexadienes are very useful building blocks for the preparation of biologically important γ-butyrolactones. Short efficient syntheses of (+)-nephrosteranic acid, (+)-trans-whisky lactone, and (+)-iram-cognac lactone by desymmetrization of 1,4-cyclohexadiene are described.
- Schleth, Florian,Vogler, Thomas,Harms, Klaus,Studer, Armido
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p. 4171 - 4185
(2007/10/03)
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- Baker's yeast-mediated approach to (-)-cis- and (+)-trans-Aerangis lactones
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The first enantioselective synthesis of natural (-)-cis-Aerangis lactone (-)-1a and its (+)-trans-diastereoisomer (+)-1b is described. The key steps in the synthesis are: (i) the enantiospecific and 100% diastereoselective baker's yeast reduction of 1,4-keto acid 2, to afford enantiopure trans-cognac lactone (+)-10; (ii) the regioselective PPL-mediated hydrolysis of the primary acetate moiety of diacetate (+)-(3S,4R)-3, obtained from (+)-10. Chain elongation by one carbon atom via cyanide substitution, and inversion of the configuration of C(5) in nitrile derivative (+)-21a are also required to complete the synthetic route to (-)-1a.
- Brenna, Elisabetta,Negri, Claudia Dei,Fuganti, Claudio,Serra, Stefano
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p. 1871 - 1879
(2007/10/03)
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- Microbial bioreductions of γ- and δ-ketoacids and their esters
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A series of yeasts were used in the bioreductions of aliphatic and aromatic γ- and δ-ketoacids and esters to investigate the preparation of enantiomerically pure γ- and δ-lactones through the intermediacy of their corresponding γ- and δ-hydroxyacids and esters. Bioreduction of ethyl 4-oxononanoate 2a with Pichia etchellsii afforded the γ-nonanolide (+)-5a with 99% e.e., while Pichia minuta proved to be the best choice for the bioreduction of ethyl 2-oxocyclohexylacetate 2e, which afforded cis-(-)-5e and trans-(-)-5e with 98 and 99% e.e., respectively. Reduction of 3-(2-oxocyclohexyl)propionic acid 3e with Pichia glucozyma gave predominantly the corresponding δ-lactone trans-(-)-6e with 94% e.e., whose absolute configuration was determined by means of CD spectroscopy.
- Forzato, Cristina,Gandolfi, Raffaella,Molinari, Francesco,Nitti, Patrizia,Pitacco, Giuliana,Valentin, Ennio
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p. 1039 - 1046
(2007/10/03)
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- Synthesis of all stereoisomers of cognac lactones via microbial reduction and enzymatic resolution strategies
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Both enantiomers of the diastereomeric cognac lactones have been synthesised using enzyme assisted reactions in the enantiodifferentiating step. This was accomplished by baker's yeast reduction of their precursors 3-methyl-4-oxononanoic acid and ester and by enzymatic hydrolysis of the latter. An inhibition of hydrolases by the products was observed. Trans-(+)-, trans-(-)-, cis-(+)- and cis-(-)-cognac lactones having 99, 88, 88 and 99% e.e., respectively, were thus obtained. Their CD spectra have also been studied.
- Benedetti, Fabio,Forzato, Cristina,Nitti, Patrizia,Pitacco, Giuliana,Valentin, Ennio,Vicario, Michela
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p. 505 - 511
(2007/10/03)
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- Enantioselective hydrogenation of β-keto sulfones with chiral Ru(II)- catalysts: Synthesis of enantiomerically pure butenolides and γ- butyrolactones
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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%.
- Bertus,Phansavath,Ratovelomanana-Vidal,Genet,Touati,Homri,Hassine, B. Ben
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p. 1369 - 1380
(2007/10/03)
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- Concise syntheses of natural γ-butyrolactones, (+)-trans-whisky lactone, (+)-trans-cognac lactone, (-)-methylenolactocin, (+)-nephrosteranic acid, and (+)-roccellaric acid using novel chiral butenolide synthons
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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)].
- Takahata,Uchida,Momose
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p. 5628 - 5633
(2007/10/03)
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- New Entry to Chiral Butenolide Synthons. Application to Expeditious Syntheses of (+)-Nephrosteranic Acid, (+)-trans-Whisky Lactone, and (+)-trans-Cognac Lactone
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A new entry to chiral butenolide synthons starting with iodolactonization of the readily available, homochiral N-benzyl-N-methyl-3-hydroxy-4-pentenamide (1) and its application to the syntheses of (+)-nephrosteranic acid (5), (+)-trans-whisky lactone (6), and (+)-trans-cognac lactone (7) are described.
- Takahata, Hiroki,Ushida, Yasuhiro,Momose, Takefumi
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p. 4123 - 4124
(2007/10/02)
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- Resolution of homoallylic alcohols containing dithioketene acetal functionalities. Synthesis of optically active γ-lactones by a combination of chemical and enzymatic methods
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Racemic homoallylic alcohols 1-3 containing dithioketeneacetal functionalities were prepared by addition of aldehydes to the allylic anions of ketene dithioacetals or 2-alkenyl-1,3-dithiane in a regio- and stereoselective manner. Lipase-catalyzed hydrolyses of the corresponding acetates 7-9 afforded optically active alcohols 1-3, which were treated with mercuric chloride to give γ-lactones such as natural hop lactone, whiskey lactone, and cognac lactone.
- Pai,Fang,Wu
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p. 6018 - 6025
(2007/10/02)
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- SYNTHESIS OF (+)-TRANS-WHISKY LACTONE, (-)-CIS-WHISKY LACTONE, (+)-COGNAC LACTONE AND (+)-ELDANOLIDE
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(+)-trans-Whisky lactone (5) and (-)-cis-whisky lactone (8), (+)-cognac lactone (9) and (+)-eldanolide (10) were sythesized starting from levoglucosenone (1) in optically pure states.
- Ebata, Takashi,Matsumoto, Katsuya,Yoshikoshi, Hajime,Koseki, Koshi,Kawakami, Hiroshi,et al.
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p. 1017 - 1026
(2007/10/02)
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- A new stereoselective route to γ-butyrolactones: Asymmetric syntheses of (+)-trans-whisky and (+)-trans-cognac lactones
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A new stereoselective route to γ-butyrolactones such as (+)-trans-whisky and (+)-trans-cognac lactones (1a,b) has been developed by a combination of three key reactions: diastereoselective nucleophilic addition of thiophenol, cleavage of chiral N-acylsultam via thioester, and intramolecular displacement of the sulfonium group with carboxylate anion.
- Miyata,Shinada,Kawakami,Taji,Ninomiya,Naito,Date,Okamura
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p. 2579 - 2581
(2007/10/02)
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- Synthesis of optically active α-trimethylsilyl Δ(α,β)-butenolides and their conversion into various butenolides and saturated γ-lactones
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Highly efficient method for synthesis of enantiomerically pure α,β-unsaturated butenolides having trimethylsilyl group at α-position (1) and their conversion into various butenolides and saturated γ-lactones are described.
- Ito,Okamoto,Sato
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p. 6399 - 6402
(2007/10/02)
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- SYNTHESIS OF (+)-TRANS-WHISKY LACTONE, (+)-TRANS-COGNAC LACTONE AND (+)-ELDANOLIDE
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A new and useful synthesis of (+)-trans-whisky lactone (3), (+)-trans-cognac lactone (4) and (+)-eldanolide (5) starting from levoglucosenone (1) is described.
- Ebata, Takashi,Matsumoto, Katsuya,Yoshikoshi, Hajime,Koseki, Koshi,Kawakami, Hiroshi,Matsushita, Hajime
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p. 1585 - 1588
(2007/10/02)
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- REACTIONS OF SOME D-RIBONOLACTONE DERIVATIVES WITH ALKYL CUPRATES. SYNTHESIS OF (+)-ELDANOLIDE AND (+)-TRANS-COGNAC LACTONE.
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Reactions of some D-ribonolactone derivatives with alkyl cuprates have been investigated in order to obtain molecules with a (4S,5R)-4,5-dialkyldihydro-2(3H)-furanone type constitution.As a direct application, (+)-eldanolide and (+)-trans-cognac lactone have been synthesized.
- Ortuno, Rosa M.,Merce, Ramon,Font, Josep
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p. 4497 - 4506
(2007/10/02)
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- Electroorganic Chemistry. Part 73. Electroreductive Cross-coupling of 3-Substituted Alkanoic Acid Esters with Aldehydes or Acid Anhydrides
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Elecroreductive cross-coupling reaction of 3-phenylthioalkanoic acids esters (4a) or quaternary ammonium salts of 3-aminoalkanoic acid esters (4b) with aldehydes gave the corresponding γ-lactones in one step.The cross-coupling reaction of (4b) with acid anhydrides leading to the formation of the corresponding γ-keto esters is also described.
- Shono, Tatsuya,Matsumura, Yoshihiro,Kashimura, Shigenori
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p. 1922 - 1935
(2007/10/02)
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