16237-62-0Relevant academic research and scientific papers
OXYGEN-INITIATED FREE-RADICAL CYANOETHYLATION OF TETRAHYDROFURAN
Galust'yan, G. G.,Glukhovtsev, V. G.
, p. 17 - 19 (1984)
Oxygen has been used as an initiator of the free-radical cyanoethylation of tetrahydrofuran by acrylonitrile.It has been shown that the initiation takes place mainly through the decomposition of tetrahydrofuran hydroperoxide, which is formed in an autooxidation of tetrahydrofuran.The initiating activity of tetrahydrofuran hydroperoxide at various temperatures has been studied.Initiation at 130 deg C is the most effective.The initiating activities of tetrahydrofuran hydroperoxide and of tert-butyl hydroperoxide have been compared.
Tetrabutylammonium decatungstate-photosensitized alkylation of electrophilic alkenes: Convenient functionalization of aliphatic C-H bonds
Dondi, Daniele,Fagnoni, Maurizio,Albini, Angelo
, p. 4153 - 4163 (2007/10/03)
Tetrabutylammonium decatungstate (TBADT, 2×10-3M) is an effective photocatalyst for the alkylation of electrophilic alkenes (0.1 M, α,β-unsaturated nitriles, esters, ketones) by alkanes, alcohols, and ethers. The products are in most cases obtained in >70% isolated yields, through an experimentally very simple procedure. The kinetics of the radical processes following initial hydrogen abstraction by excited TBADT in deoxygenated MeCN have been studied. In the absence of a trap, back hydrogen transfer from reduced tungstate is the main pathway for alkyl radicals, while α-hydroxyalkyl radicals are oxidized to ketones by ground-state TBADT. With both radical types the reaction ceases at a few percent conversion. However, trapping by electrophilic alkenes is followed by reduction of the radical adduct and regeneration of the catalyst, which allows the alkylation to proceed up to complete alkene conversion with the mentioned good yields of products. With a nucleophilic (α-hydroxyalkyl) radical, alkylation is efficient (Φ = 0.58) and can also be carried out when degassing is omitted, the only difference being a short induction period. With a less reactive (cyclohexyl) radical, the quantum yield is lower (Φ = 0.06) and the reaction is considerably slowed in aerated solutions, but the chemical yield remains good.
Radical addition of 2-iodoalkanamide or 2-iodoalkanoic acid to alkenes with a water-soluble radical initiator in aqueous media: Facile synthesis of γ-lactones
Yorimitsu,Wakabayashi,Shinokubo,Oshima
, p. 1963 - 1970 (2007/10/03)
Radical reactions in water or aqueous ethanol using a water-soluble radical initiator are described. Heating a mixture of 2-iodoacetamide and 5-hexen-1-ol in water at 75 °C in the presence of a water-soluble radical initiator, 4,4′-azobis 4-cyanopentanoic acid), afforded 5-(4-hydroxybutyl)dihydrofuran-2(3H)-one in 95% yield. The use of 2-iodoacetic acid in place of 2-iodoacetamide also gave the same γ-lactone in 93% yield. The reaction of 2-iodoacetamide with 1-octene in aqueous ethanol was initiated by 2,2′-azobis(2-methylpropanamidine) dihydrochloride to provide γ-decanolactone. Employing water as a solvent is crucial to obtain lactone in satisfactory yield.
Deplacement homolytiques intramoleculaires. 14. Additions radicalaires a des peroxydes de δ-alcenyle et de tert-butyle : acces a des tetrahydrofurannes et des tetrahydropyrannes substitues
Agorrody, M.,Montaudon, E.,Maillard, B.
, p. 2694 - 2700 (2007/10/02)
Free radical additions of hydrogen donors of type ZH to δ-unsaturated organic peroxides give 5- or 6-membered cyclic ethers in yields varying from 40 to 70percent, depending on the substitution of the double bond.
