80277-59-4Relevant academic research and scientific papers
Nucleophilic substitution of 5,5-dimethyl-2-cyclopentenyl derivatives. Lack of SN2' reaction
Kopecky, Karl R.,Levine, Cyril
, p. 3273 - 3279 (2007/10/02)
Treatment of tetramethyl-1,3-cyclobutadienone with two equivalents of allyl oxide anion at 140 deg C yields 2,2-dimethyl-4-pentenoic acid which is cyclized via the acid chloride whith aluminium chloride to 5,5-dimethyl-2-cyclopentenone 4.Reduction of 4 with aluminium hydride provides 5,5-dimethyl-2-cyclopentenol 1-OH which is pyrolyzed to 5,5-dimethyl-1,3-cyclopentadiene in dimethylsulfoxide.Reduction of 4 with tri-t-butoxyaluminium hydride at -70 deg C gives 2,2-dimethylcyclopentanone.The 2,6-dichlorobenzoate ester of 1-OH failed to yield SN2' products under a variety of conditions.The rate constants for solvolysis of the p-nitrobenzoate esters of 1-OH, 2-cyclopentenol and Z-2-methyl-4-hexene-3-ol in 80 percent ethanol at 80 deg C are 20.2, 523, and 0.63 x 1E-6s-1, respectively, and the main products of solvolysis are 5-ethoxy-3,3-dimethylcyclopentene, 3-ethoxycyclopentene, and E-2-ethoxy-5-methyl-3-hexene, respectively.There is steric hindrance to solvatation during ionization of the p-nitrobenzoate of 1-OH.
