5674-05-5Relevant academic research and scientific papers
Beryllium dichloride: Efficient promoter for the addition of organolithiums and organomagnesiums to cyclohexen-2-one
Krief, Alain,De Vos, Marie Joelle,De Lombart, Stephane,Bosret, Jean,Couty, Francois
, p. 6295 - 6298 (2007/10/03)
Organoberyllium compounds, generated by transmetallation from Grignard and organolithium reagents react with 2-cyclohexenone to give predominantly the adducts resulting from conjugated addition. The chemoselectivity of this reaction was found to be highly dependent upon the nature of organic moiety and of the conditions used.
The photochemistry of 3-nitro-2-cyclohexenone
Quevillon, Tracy M.,Weedon, Alan C.
, p. 3939 - 3942 (2007/10/03)
3-Nitro-2-cyclohexenone appears to be unreactive when irradiated with ultra-violet light; no rearrangement of the nitro group to a nitrite ester or dimerization of the enone to cyclobutane adducts was observed. Cyclobutane containing photoadducts are also not formed when the electron poor alkenes, acrylonitrile or methyl acrylate are present. However, cyclobutane adducts are produced with more electron rich alkenes. The cycloadducts from reaction with cyclopentene can be reduced with zinc and acid to give a cyclooctanedione identical with the product of de Mayo reaction of cyclohexane-1,3-dione with cyclopentene. Photoadducts are also formed with 2-methylpropene; treatment of these with AIBN followed by hydrogenation yields products identical with those produced by hydrogenation of the photoadducts formed from ultra-violet light irradiation of 2-cyclohexenone with 2-methylpropene. The presence of the nitro group on the cyclohexenone increases the proportion of the head-to-head regioisomers from 13% of the adduct mixture to 63%. Copyright
A Facile Synthesis of Bicycloalkan-1-ols. Evidence for Organosamarium Intermediates in the Samarium(II) Iodide Promoted Intramolecular Barbier-Type Reaction
Molander, Gary A.,McKie, Jeffrey A.
, p. 4112 - 4120 (2007/10/02)
Samarium(II) iodide (SmI2) has been successfully employed as a reductive coupling agent for the intramolecular Barbier-type synthesis of bicycloalkan-1-ols.Thus, a variety of 3-(ω-iodoalkyl)cycloalkanones, upon treatment with SmI2 and a catalytic q
1,4-Addition of Triorganozincates and Silyldiorganozincates to α,β-Unsaturated Ketones
Tueckmantel, Werner,Oshima, Koichiro,Nozaki, Hitosi
, p. 1581 - 1593 (2007/10/02)
Lithium and magnesium triorganozincates, prepared by combination of ZnCl2(TMEDA) with 3 molar equivalents of RLi or RMgX, or from dialkylzinc and 1 molar equivalent of RLi or RMgX, react with 2-cyclohexen-1-one (1) under mild conditions to produce moderate to good yields of the 1,4-addition products 2.The approximate reactivity order obtained from the product distribution using unsymmetrical zincates is tBuCH2 tBu, Me Me2PhSi.The latter groups are transferred with good selectivity from mixed reagents derived from Me2Zn.This sequence differs strikingly from that exhibited by unsymmetrical cuprates which transfer neopentyl very easily, and also tert-butyl more easily than the corresponding zincates.The methylation with Me3ZnLi is catalyzed by cobalt complexes.Other enones (7-13) generally give poor yields, and the cobalt-catalyzed methylation of isophorone (3) is complicated by a Kharasch-type deconjugation.Mixed silyldialkylzincates, Me2PhSiZnR2Li, produce the β-silyl ketones from a variety of unhindered or moderately hindered enones in practically useful yields; one example of an α,β-unsaturated ester (12) is also included.
