42117-29-3Relevant academic research and scientific papers
Superoxide Anion Radical (O2)-radical Mediated Base-Catalyzed Autoxidation of Enones
Frimer, Aryeh A.,Gilinsky-Sharon, Pessia,Aljadeff, Gladis,Gottlieb, Hugo E.,Hameiri-Buch, Judith,et al.
, p. 4853 - 4866 (2007/10/02)
Seventeen variously substituted cyclohex-2-en-1-ones were prepared and reacted with superoxide anion radical (O2-radical generated from KO2/18-crown-6) in inert nonpolar aprotic media at room temperature.The 4,4,6,6-tetrasubstituted cyclohexenones (1b,1c, and 1d) proved to be totally inert,while those cyclohexenones possessing available acidic α'- or γ-hydrogens underwent O2-radical mediated base-catalysed autoxidation (BCA) generating various products depending on the nature and location of the substituents.Thus, 4,4- and 5,5-disubstituted substrates(2b, 2c, 2e, 2f and 3b, 3d, 3f-3i, respectively) gave 2-hydroxycyclohexa-2,5-dien-1-ones (7) as the major product (>80percent yield) upon aqueous acid workup while the corresponding 2-methoxy analogues 8 are obtained when the reaction is quenched with CH3I. 2,3-Epoxycyclohexanones 13 and oxidative cleavage products 11 and 12 are formed in the case of the 6,6-disubstituted systems (4a-4c); these oxidation products are accompanied by dimers 14 when the substituent on 4 is CH3 or H.Epoxide 23 is the primary isolable product in the 3,4,4-trialkyl system (5d).As expected for BCA processes, similar results were observed when these reactions were mediated by KOH (at room temperature) or KOC(CH3)3 (at -40 deg C).In the case of 6,6-diphenylcyclohex-2-en-1-one (4c), however, tert-butoxide-mediated BCA at -40 deg C yielded cyclopentene hydroxy acid 15 in addition to epoxide 13.The saturated analogue of 4c, 18, yielded primarily the corresponding saturated hydroxy acid 19, as well as several other oxidation products (20-22) depending on the reaction conditions.The mechanism of these transformations is rationalized in terms of base-induced reactions and rearrangements of the initially formed keto hydroperoxides.
Nitration of 2-Cyclohexenone Derivatives and Some Reactions of the Products
Matoba, Katsuhide,Morita, Takashi,Yamazaki, Takao
, p. 4368 - 4375 (2007/10/02)
5,5-dimethyl-2-cyclohexenone (Ia) and isophorone (Ib) were nitrated with isoamyl nitrate using potassium metal in liquid ammonia to give 5,5-dimethyl-2-nitro-1,3-cyclohexadienol (III) and 3,5,5-trimethyl-2-nitro-2-cyclohexenone (IVb), respectively.Compoun
Preparation of oxacycloalkenones
-
, (2008/06/13)
Oxacycloalkenones are prepared by reacting a cycloalkenone with a base in the presence of a dioxygen source in a suitable solvent and isolating the desired product. 1-Hydroxy 2-oxa-3-oxo-Δ4 steroids are convenient synthetic precursors to 2-oxa-
A FACILE SYNTHESIS OF 2-METHOXY-4,4-DIMETHYL-2,5-CYCLOHEXADIENONE VIA 5,5-DIMETHYL-2-NITRO-1,3-CYCLOHEXADIENOL
Matoba, Katsuhide,Yamazaki, Takao
, p. 3863 - 3864 (2007/10/02)
5,5-Dimethyl-2-nitro-1,3-cyclohexadienol(I), which was prepared from 5,5-dimethyl-2-cyclohexenone(IIa), afforded 5,5-dimethyl-2-hydroxyimino-3-cyclohexenone(VIII) by reaction with diazomethane.VIII was hydrolyzed to 2-hydroxy-5,5-dimethyl-2,5-cyclohexadienone(Vb) via nitrone(X).Vb was methylated to III by treating with dimethyl sulfate.The yield of III from VIII was satisfiable.KEYWORDS - 2-nitro-1,3-cyclohexadienol; 2-nitro-2-cyclohexenone; 2-hydroxyimino-3-cyclohexenone; 2-methoxy-2,5-cyclohexadienone; diazomethane; hydrolysis
THE REACTION OF ENOLS WITH SUPEROXIDE ANION RADICAL 2-.>. SYNTHESIS OF 2,3-UNSATURATED-δ-VALEROLACTONES.
Frimer, Aryeh A.,Gilinsky-Sharon, Pessia,Aljadeff, Gladis
, p. 1301 - 1304 (2007/10/02)
3- and 4-Hydroxycoumarin (1 and 3) as well as 2-hydroxy-2,5-cyclohexadien-1-ones 5a-f were reacted with KO2/18-crown-6 in benzene.Initial deprotonation of the enol hydrogen was followed by nucleophilic attack by O2> (for 1 and 3) and/or autoxidation of the resulting anion (for 1 and 5a-e).A convenient synthesis of 2,3-unsaturated-δ-valerolactones from the corresponding 2-cyclohexen-1-ones is also described.
