4435-19-2Relevant articles and documents
Samarium (II) iodide-induced intermolecular coupling of a,b-unsaturated esters with ketones: Reactions of methyl propiolate and ethyl buta-2,3-dienoate with cyclohexanone and its application to synthesis of a terpene carboxylic acid
Sono, Masakazu,Doi, Natsuki,Yoshino, Eri,Onishi, Sachiko,Fujii, Daiki,Tori, Motoo
supporting information, p. 1947 - 1950 (2013/04/10)
The reactions of methyl propiolate and ethyl buta-2,3-dienoate with cyclohexanone induced by SmI2 occurred either at a- or b-position to yield different products depending on with or without a proton source. The synthesis of terpenic acid was demonstrated using this reaction.
The reaction of photochemically generated α-hydroxyalkyl radicals with alkynes: a synthetic route to γ-butenolides
Geraghty, Niall W.A.,Hernon, Elaine M.
scheme or table, p. 570 - 573 (2009/05/07)
The photomediated generation of α-hydroxyalkyl radicals from simple acyclic and cyclic alcohols, and acyclic diols, and their subsequent carbon-carbon bond forming reaction with propiolate esters and acetylenedicarboxylates, gives a mixture of a β-(hydroxyalkyl)enoate, the result of a formal cis addition, and the unsaturated lactone (γ-butenolide) resulting from the spontaneous cyclization of the corresponding trans addition product. Treatment of the cis adduct with NBS converts it to the same lactone, and so the method overall constitutes a particularly direct route to this important structural unit. Cyclic alcohols give rise to spiro-γ-butenolides. The use of supported photomediators simplifies product isolation and allows for the recovery and reuse of the photomediator.
Trans-selective conversions of γ-hydroxy-α,β-alkynoic esters to γ-hydroxy-α,β-alkenoic esters
Meta, Christopher T.,Koide, Kazunori
, p. 1785 - 1787 (2007/10/03)
Matrix presented. γ-Hydroxy-α,β-acetylenic esters are used as precursors to prepare γ-hydroxy-α,β-alkenoic esters by means of trans-selective additions of two hydrogen atoms or one hydrogen atom and one iodine atom across the triple bonds. These methods a
Palladium(II) Chloride Catalyzed Carbonylation of Organic Tellurides with Carbon Monoxide
Ohe, Kouichi,Takahashi, Hidetaka,Uemura, Sakae,Sugita, Nobuyuki
, p. 4859 - 4863 (2007/10/02)
Various organic tellurides react with carbon monoxide (1 atm) at room temperature in methanol in the presence of PdCl2 and Et3N to afford the corresponding methyl carboxylates in good to excellent yields.The reaction is catalytic in PdCl2 when a suitable reoxidant such as CuCl2, CuCl/O2, FeCl3 or Ce(NH4)2(NO3)6 is present.The combination of this carbonylation with phenyltellurenylation of arylacetylenes and propargylic alcohols makes it possible to prepare ring-substituted cis-methyl cinnamates and Δα,β-butenolides, respectively.Both monomeric and dimeric palladium complexes, (Ph2Te)2PdCl2 and 2, react readily with CO to give a high yield of methyl benzoate.The key step of the present carbonylation is proposed to be the migration of an organic moiety from Te to Pd (transmetalation) in organic telluride-PdCl2 complexes, presumably formed in situ, to afford organopalladium compounds.
Novel Synthesis of Five- and Six-Membered Spiro γ-Lactones in Rigid Bicyclic Systems
Cannone, Persephone,Belanger, Denis,Lemay, Gilles
, p. 3953 - 3959 (2007/10/02)
The reaction of bis(bromomagnesio)alkanes with bridged tricyclic endo- and exo-dicarboxylic anhydrides and their dihydro derivatives provides a general and versatile route to corresponding tricyclic spiro γ-butanolides.Futher extension of this methodology to the dianhydride of bicyclooctene showed appreciable regioselectivity.The subsequent transformation of spiro γ-lactones into 4-spiro-2-butenolides by retro-Diels-Alder reaction has provided a simple and convenient synthesis of these molecules.Proton and 13C NMR spectra are reported for most of the compounds.
