The influence of hydrogen bonding on the solvolytic reactivity of nicotinates in fluorinated alcohols
作者:Branko Juršić、Dionis E. Sunko、Mladen Ladika
DOI:10.1016/s0040-4020(01)90312-6
日期:1987.1
A systematic investigation of solvolyticreactivities of allylic and benzylic nicotinates and their N-methylated derivatives in 80% EtOH, 97% TFE and 97% HFIP was undertaken. The nicotinates in 97% HFIP are slightly more reactive than the corresponding p-nitrobenzoates, whereas the ratio of these reactivities is inverse in 80% EtOH and 97% TFE. This observation was explained by the stronger hydrogen
A Novel Tandem [2 + 2] Cycloaddition−Dieckmann Condensation with Ynolate Anions. Efficient Synthesis of Substituted Cycloalkenones and Naphthalenes via Formal [<i>n</i> + 1] Cycloaddition
作者:Mitsuru Shindo、Yusuke Sato、Kozo Shishido
DOI:10.1021/jo015929w
日期:2001.11.1
A noveltandem [2 + 2] cycloaddition-Dieckmanncondensation via ynolate anions is described. Ynolate anions are useful for the formation of reactive beta-lactone enolates via a pathway not involving the enolization of the corresponding beta-lactones. The [2 + 2] cycloaddition of ynolate anions with delta- or gamma-keto esters, followed by Dieckmann condensation, gives bicyclic beta-lactones, which
Ethyl 2- methyl-4-oxocyclohex-2-enecarboxylate (Hagemann's ester) as a precursor to alkyl-substituted 3-methylcyclohexenones
作者:Bruce A. McAndrew
DOI:10.1039/p19790001837
日期:——
from ethyl 2-methyl-4-oxocyclohex-2-enecarboxylate (Hagemann's ester)via the alkylation of its ethylene glycol acetal. Various routes to 6-alkyl-3-methylcyclohex-2-enones from Hagemann's ester have been explored; a particularly convenient route to these unsaturated ketones utilised the isomeric keto-ester, ethyl 4-methyl-2-oxocyclohex-3-enecarboxylate as starting material. The alkylation of ethyl 2-
Zn(II)- or Rh(I)-Catalyzed Rearrangement of Silylated [1,1′-Bi(cyclopropan)]-2′-en-1-ols
作者:Hang Zhang、Changkun Li、Guojun Xie、Bo Wang、Yan Zhang、Jianbo Wang
DOI:10.1021/jo5010923
日期:2014.7.3
The rearrangement reactions of silylated alcohols bearing the highly strained structures of cyclopropene and cyclopropanol connected in adjacent positions have been studied under ZnI2- and Rh(I)-catalyzed conditions. The results show intriguing carbon skeletal reorganizations of such system under these conditions. The ZnI2-catalyzed reaction proceeds with C–O cleavage and the rearrangement of the resultant
Reaction of cyclic .alpha.-hydroxy epoxides with a strong base: a new 1,2-rearrangement, evidence for a carbenoid pathway.
作者:Eric Doris、Luc Dechoux、Charles Mioskowski
DOI:10.1021/ja00156a006
日期:1995.12
Several substituted five- and six-membered cyclic alpha,beta-unsaturated ketones are readily available by treatment of the corresponding alpha-hydroxy epoxides with an organolithium reagent. The reaction involves a new carbenoid 1,2-alkyl rearrangement. Evidence for the carbenoid intermediate has been obtained by an intramolecular trapping of the highly reactive species.