22173-37-1Relevant academic research and scientific papers
A highly efficient asymmetric synthesis of optically active α,γ-substituted γ-butyrolactones using a chiral auxiliary derived from isosorbide
Xu, Ming-Hua,Wang, Wei,Lin, Guo-Qiang
, p. 2229 - 2232 (2000)
(equation presented) Using an easily accessible and inexpensive chiral auxiliary derived from isosorbide, optically active α,γ-substituted γ-butyrolactones were obtained in high enantiomeric purity (up to >99% ee for trans) by the Sml2-induced
Electroreductive coupling of aromatic ketones, aldehydes, and aldimines with α,β-unsaturated esters: Synthesis of 5-aryl substituted γ-butyrolactones and lactams
Kise, Naoki,Hamada, Yusuke,Sakurai, Toshihiko
, p. 1143 - 1156 (2017/02/18)
The electroreductive intermolecular coupling of aromatic ketones and aldehydes with α,β-unsaturated esters in the presence of TMSCl gave the adducts as γ-trimethylsiloxy esters. The detrimethylsilylation of the adducts with TBAF afforded 5-aryl substituted γ-butyrolactones. The electroreductive coupling of N-(4-methoxyphenyl)-1-arylmethaneimines with methyl acrylate in the presence of TMSCl gave the adducts as methyl 4-aryl-4-((4-methoxyphenyl)amino)butanoates. The adducts were transformed to 5-aryl-γ-butyrolactams by cyclization with NaH and subsequent oxidation with CAN. (±)-Norcotinine was prepared from nicotinaldehyde by this method. The electroreductive coupling of aromatic ketones and aldimines with acrylonitrile in the presence of TMSCl gave 4-aryl-4-(trimethylsiloxy)butanenitriles and 4-aryl-4-((4-methoxyphenyl)amino)butanenitriles, respectively.
Copper-Catalyzed Formal [2+2+1] Heteroannulation of Alkenes, Alkylnitriles, and Water: Method Development and Application to a Total Synthesis of (±)-Sacidumlignan D
Ha, Tu M.,Chatalova-Sazepin, Claire,Wang, Qian,Zhu, Jieping
supporting information, p. 9249 - 9252 (2016/08/05)
A copper-catalyzed three-component reaction of alkenes, alkylnitriles, and water affords γ-butyrolactones in good yields. The domino process involves an unprecedented hydroxy-cyanoalkylation of alkenes and subsequent lactonization with the creation of three chemical bonds and a quaternary carbon center. The synthetic potential of this novel [2+2+1] heteroannulation reaction was illustrated by a concise total synthesis of (±)-sacidumlignan D.
A new synthesis of lactones from tertiary alkenylcarbinols by cobalt-catalyzed photocarbonylation under ambient conditions
Chow, Yuan L.,Huang, Yu-Jin,Dragojlovic, Veljko
, p. 740 - 742 (2007/10/02)
In the presence of a Co catalyst, tertiary vinyl-, propenyl-, and allylcarbinols were chelatively cycloadded to carbon monoxide to produce lactones by xanthone-sensitized photoreaction in tetrahydrofuran, under CO at 1 atmosphere and at room temperature.At lower temperatures the isomerization of alkenyl-carbinols was suppressed and lactones were obtained with improved selectivity.The photoprocess was facilitated by addition of pyridine or hydrogen and retarded in presence of amines or phosphines.Mechanistic interpretations for the process and the accompanying effects are discussed.Key words: chelative carbonylation, photocarbonylation, carbonylation of olefins, lactones synthesis from alkenylalcohols.
Trimethylsilyl Cyanide - A Reagent for Umpolung, XX. - On the Regioselectivity of the Addition of Carbonyl Compounds to α,β-Unsaturated Aldehydes after Umpolung
Huenig, Siegfried,Schaefer, Matthias
, p. 177 - 190 (2007/10/02)
By addition of tBuMe2SiCN to α,β-unsaturated aldehydes 5 the silylated cyanohydrins 6 are produced.Deprotonation of 6 provides allylic anions which can be attached to aldehydes and ketones in α-position (kinetic control) (-> 8) or γ-position (thermodynamic control) (-> 9).In contrast to the Me3Si group which has been applied so far the tBuMe2Si group is stable under the reaction conditions.Therefore, the ratio of α/γ adducts can be tuned from > 95:5 to 5:95 depending on the substitution pattern of 6, the aldehydes and ketones, the reaction time and temperature, and even by some additives.The γ adducts 9 are easily transformed into γ-butyrolactones 27 by acidic hydrolysis. Key Words: Umpolung / Regioselectivity / Substituent effects / Acylation, nucleophilic / Aldehydes, α,β-unsaturated / Trimethylsilyl cyanide
Samarium(II) Di-iodide Induced Reductive Coupling of α,β-Unsaturated Esters with Carbonyl Compounds Leading to a Facile Synthesis of γ-Lactone
Fukuzawa, Shin-ichi,Nakanishi, Akira,Fujinami, Tatsuo,Sakai, Shizuyoshi
, p. 1669 - 1676 (2007/10/02)
Samarium(II) di-iodide, which is a strong one-electron transfer reducing agent, is effective for the reductive coupling of α,β-unsaturated esters with carbonyl compounds, whereby substituted γ-lactones can easily be prepared in good to excellent yields under very mild conditions.Two mole equiv. of samarium(II) di-iodide to each mole equiv. of starting substrate always give reasonable yields.The presence of an alcohol is essential in the reaction, complex unidentified products being formed in the absence of an alcohol; t-butyl alcohol gave more satisfactory results than methanol and ethanol.The alcohol acts as a proton donor, the use of MeOD leading to a deuteriated γ-lactone.The reaction is applicable to both aliphatic and aromatic ketones or aldehydes, whereas the electrochemical method is limited to aliphatic substrates.The diastereoselectivity is examined in the reaction of 4-t-butylcyclo-hexanone with ethyl acrylate; an anti-isomer is produced predominantly (syn:anti = 1:9) as the result of selective axial attack.The reaction may proceed by a radical mechanism, and reaction may not involve a samarium ester homoenolate.The reaction is extended to the intramolecular reaction of an α,β-unsaturated keto ester (8-oxonon-2-enoate) leading to the ready synthesis of a bicyclic γ-lactone.
ELECTRON-TRANSFER PROCESSES. NEW SYNTHESIS OF γ-LACTONES BY PEROXYDISULFATE OXIDATION OF ISOPROPYLBENZENES AND ALIPHATIC CARBOXYLIC ACIDS
Giordano, Claudio,Belli, Aldo,Citterio, Attilio,Minisci, Francesco
, p. 3559 - 3562 (2007/10/02)
A new synthesis of γ-lactones by peroxydisulfate oxidation of isopropylbenzenes is described.Evidence concerning the free-radical mechanism is reported; the intermediate formation of alkyl and benzyl radicals is evidenced by trapping them with quinoxaline.The role of the iron catalyst is discussed.
