65726-91-2Relevant academic research and scientific papers
1,2-DERIVATIVES OF ACENAPHTHYLENE. IX. NEW DATA ON ADDITION OF HALOGENS TO ACENAPHTHYLENE
Anikin, V. F.,Levandovskaya, T. I.
, p. 961 - 966 (2007/10/02)
Acenaphthylene adds molecular halogens nonstereospecifically.The relative amount of the Z-dihalide increases with decrease in the polarity of the solvent.Z-1,2-dibromo-1,2-dihydroacenaphthylene is not changed after a year at 4-6 deg C; the best solvent for its production is hexane.
Phenylselenium Trichloride in Organic Synthesis. Reaction with Unsaturated Compounds. Preparation of Vinylic Chlorides via Selenoxide Elimination
Engman, Lars
, p. 4086 - 4094 (2007/10/02)
Phenylselenium trichloride, PhSeCl3, was reacted with a number olefinic compounds to produce (β-chloroalkyl)phenylselenium dichlorides.The addition was anti stereospecific and irreversible.The presence of an oxygen substituent (acyloxy or aryloxy group) in the allylic position of the olefin directed the attack of PhSeCl3 to occur regiospecifically anti-Markovnikov to give a (β-acyloxy/aryloxy-β'-chloroalkyl)phenylselenium dichloride.When the (β-chloroalkyl)phenylselenium dichlorides were treated in methylene chloride with aqueous sodium hydrogen carbonate, the selenium dichloride moiety was readily hydrolyzed to a selenoxide, which underwent the usual selenoxide elimination reaction to produce an allylic or a vinylic chloride.Symmetrical olefins containing no allylic hydrogens were converted to vinylic chlorides with retention of olefin geometry.Olefins containing a directing oxygen substituent in the allylic position afforded vinylic chlorides where the vinylic halogen atom was oriented 1,3 to the oxygen substituent (E/Z mixture).Other olefins afforded mixtures of allylic and vinylic halides in varying proportions.The reaction of phenyselenium tribromide, PhSeBr3, with some olefinic compounds was also investigated.This material showed the same stereo- and regiochemical behavior as PhSeCl3 in its addition reactions.However, the adducts were not useful for the preparation of vinylic or allylic bromides by using the hydrolytic selenoxide elimination reaction.
Concerted and Stepwise Mechanisms in the Eliminations from 1,2-Dihalogenoacenaphthenes Promoted by Potassium tert-Butoxide and Potassium Ethoxide in the Corresponding Alcohols
Baciocchi, Enrico,Ruzziconi, Renzo,Sebastiani, Giovanni Vittorio
, p. 3237 - 3241 (2007/10/02)
Anti and syn eliminations from cis- and trans-dihalogenoacenaphthenes, respectively, have been investigated in t-BuOK-t-BuOH and EtOK-EtOH.The leaving group ability order for the syn eliminations in t-BuOK-t-BuOH is F > Cl ca.Br, which suggests an (E1cB)I mechanism.Also consistent with this mechanism is the observation that from trans-1-chloro-2-fluoroacenaphthene only HF is eliminated.In EtOK-EtOH the order of leaving group ability for the syn eliminations is Br > Cl > F, which might suggest an E2 mechanism; however, the leaving group effects are very small, anda stepwise mechanism cannot be excluded.The anti eliminations from the cis-dihalogenoacenaphthenes exhibit a substantial leaving group effect; on this basis and also on considering the β-halogen effect on the rate of elimination, a concerted mechanism is suggested.
Synthesis of New Functional Acenaphthylene Derivatives. 2. Regioselective Electrophilic Substitution of Silylated Acenaphthenes and Acenaphthylenes
Felix, Guy,Laguerre, Michel,Dunogues, Jacques,Calas, Raymond
, p. 1423 - 1427 (2007/10/02)
New silylated derivatives have been synthesized in the acenaphthylene series by appropriate silylation reactions, followed by oxidation in the case of 3a. 1a and 3a as well as 1-(trimethylsilyl)-and 1,2-and 1,5-bis(trimethylsilyl)acenaphthylenes (2a, 4a, and 5a, respectively) have been used as regioselective precursors of 5-functional acenaphthenes and 1-monofunctional and 1,2-and 1,5-bifunctional acenaphthylenes by electrophilic substitution of the trimethylsilyl group(s).Mono- and bisulfonations succeeded in all cases as well as the acylation or iodination of monosilyl derivatives and 1,2-diodination of 4a.Thus, various novel functional acenaphthenes and acenaphthylenes could be prepared by a convenient route.In contrast, attempts at diodination of 5a and diacylation of 4a and 5a were unsuccessful.
Irreversible E1cb Mechanism in the syn Eliminations from 1,2-Dihalogenoacenaphthenes Promoted by Potassium t-Butoxide in t-Butyl Alcohol
Baciocchi, Enrico,Ruzziconi, Renzo,Sebastiani, Giovanni V.
, p. 807 - 808 (2007/10/02)
The lack of a significant leaving group effect and the preferential departure of the "poorer" leaving group suggest an irreversible E1cb mechanism for the title reactions.
