1655-03-4Relevant articles and documents
Hydration of aromatic terminal alkynes catalyzed by sulfonated condensed polynuclear aromatic (S-COPNA) resin in water
Tanemura, Kiyoshi,Suzuki, Tsuneo
supporting information, p. 955 - 958 (2017/02/18)
Hydration of aromatic terminal alkynes in the presence of a catalytic amount of sulfonated condensed polynuclear aromatic (S-COPNA) resin in water gave the corresponding methyl ketones in good yields. On the other hand, aliphatic terminal alkynes did not react at all under the employed conditions. Chemoselective hydration of aromatic terminal alkyne in the presence of aliphatic terminal alkyne catalyzed by S-COPNA resin was carried out.
Nazarov cyclization of divinyl ketones bearing an ester group at the β-position: A remarkable effect of α-substitution and alkene geometry on regioselectivity
Sudhakar, Gangarajula,Raghavaiah, Jakka,Mahesh, Gaddam,Singarapu, Kiran Kumar
supporting information, p. 2866 - 2872 (2016/03/12)
The Nazarov cyclization of divinyl ketones with an ester at the β-position was examined with particular reference to where the cyclic double bond forms. We observed unprecedented regioselectivity, dictated by the subtle substitution patterns at the α-position and alkene geometry of α,β and mostly, this selectivity is regardless of substitutions at α′- and β′-positions. The major implications of these observations are an aromatic group at the α-position with E-olefin geometry provides a cyclopentenone in which the double bond is not in conjugation with an ester, whereas Z-olefin provides a cyclopentenone in which the double bond is in conjugation with an ester; and divinyl ketones bearing an ester group at the β-position and an alkyl group at the α-position with E-olefin geometry provide a cyclopentenone in which the double bond is in conjugation with the ester.
Iron Catalyzed Highly Enantioselective Epoxidation of Cyclic Aliphatic Enones with Aqueous H2O2
Cussó, Olaf,Cianfanelli, Marco,Ribas, Xavi,Klein Gebbink, Robertus J. M.,Costas, Miquel
supporting information, p. 2732 - 2738 (2016/03/12)
An iron complex with a C1-symmetric tetradentate N-based ligand catalyzes the asymmetric epoxidation of cyclic enones and cyclohexene ketones with aqueous hydrogen peroxide, providing the corresponding epoxides in good to excellent yields and enantioselectivities (up to 99% yield, and 95% ee), under mild conditions and in short reaction times. Evidence is provided that reactions involve an electrophilic oxidant, and this element is employed in performing site selective epoxidation of enones containing two alkene sites.
Induced halogenation of alkyl cyclohexenyl ketones involving metal halides, hydrohalogenic acids, and hydrogen peroxide
Sadygov,Alimardanov
experimental part, p. 166 - 172 (2009/09/25)
The induced halogenation and hydroxyhalogenation of alkyl cyclohexenyl ketones in a system [MHlg + HHlg or HHlg]-H2O2 or in NaOCl was performed and optimum reaction conditions were established. Under mild conditions the electrophilic addition of the halogen or the acid occurred at the multiple bond of the ring with the formation of the corresponding dihalo or hydroxyhalo derivatives of cycloaliphatic ketones. From the compounds obtained epoxy- and dioxyketones of aliphatic series were prepared. Chloro(bromo)hydrins of ketones from the alkylcyclohexane series and oxiranes based thereon are reactive compounds and can be employed as synthons in the organic synthesis.
Novel Acylation of Aliphatic Olefins Promoted by Active Zinc Compounds
Shono, Tatsuya,Nishiguchi, Ikuzo,Sasaki, Manji,Ikeda, Haruhiko,Kurita, Makoto
, p. 2503 - 2505 (2007/10/02)
It was found that acylation of a variety of aliphatic olefins with acid chlorides is efficiently promoted by active zinc compounds, which were prepared from a Zn/Cu couple and alkyl iodides.The crude product mixtures were subsequently treated with 1 M KOH in methanol or were subjected to catalytic hydrogenation to afford the corresponding α,β-unsaturated or saturated ketones in good to moderate yields.It was also shown that the reaction fully follows the Markovnikov rule.
Vinyl Cations, 37. Rearrangement of Cyclic Homopropargyl Sulfonates to Condensed Cyclobutanones and Cyclopropyl Ketones
Hanack, Michael,Schuhmacher, Werner,Kunzmann, Erich
, p. 1467 - 1487 (2007/10/02)
Cyclic homopropargyl sulfonates 8 (tosylates, triflates, nonaflates, and damsylates) are prepared and solvolysed.The resulting rearrangement reactions are studied with respect to the properties of the solvents used, leaving groups, the substituent on the triple bond, and with respect to the ring size of the sulfonates 8.
GEM-DISILYLCYCLOPROPANES: PREPARATION ET UTILISATION EN SYNTHESE ORGANIQUE
Laguerre, Michel,Grignon-Dubois, Micheline,Dunogues, Jacques
, p. 1161 - 1169 (2007/10/02)
A simple general route for the conversion of olefins to gem-disilylcyclopropanes, involving the dichlorocyclopropanation of the double bond followed by silylation using the Me3SiCl/Li/THF reagent at 0-10 deg C, is described.Acetylation of bicyclic derivatives thus obtained constitutes an original synthesis of cycloalkylidene ketones by a process more convenient than those previously used, and also provides new acetyl dihydrofurans.
