126235-81-2

Upstream product

• 14804-25-2 tert-butyl cation 
• 103-63-9 1-phenyl-2-bromoethane 
• 29180-23-2 p-fluorobenzyl ion 

Downstream Products

• 14804-25-2 tert-butyl cation 
• 103-63-9 1-phenyl-2-bromoethane 
• 21410-12-8 2-adamantanyl cation 

Relevant academic research and scientific papers

Thermodynamic Stabilities of Phenonium Ions Based on Bromide-Transfer Equilibria in the Gas Phase

The thermodynamic stabilities of the phenonium (ethylenebenzenium) ion and ring-substituted derivatives were determined based on the bromide-transfer equilibria in the gas phase. It has been shown that the phenonium ion is 2.4 kcal mol-1 more stable than the t-butyl cation, and that the substituent effect on its stability can be correlated with the Yukawa-Tsuno equation with a ρ value of -12.6 and an r+ of 0.62. An r+ value smaller than unity of the α-cumyl(1-methyl-1-phenylethyl) cation suggested that π-delocalization in the phenonium ion is essentially less effective than through a benzylic π-interaction. On the other hand, the ρ value of -12.6 is distinctly larger than that for the ordinary benzylic carbocation systems, but is comparable to that of the benzenium ion. In addition, it has been found that the r+ value of the phenonium ions in the gas phase is in complete agreement with that for the aryl-assisted process in the acetolysis of 2-arylethyl toluenesulfonates. This suggests that the degree of π-delocalization of the positive charge is the same in the transition state and the intermediate cation. It is concluded that an r+ value of 0.6, which is ranked at a unique position in the continuous spectrum of the resonance demand, is characteristic of the bridged structure of the phenonium ion intermediate and the transition state.

Thermodynamic Stabilities of Phenonium Ions in the Gas Phase

Gas phase stabilities of substituted phenonium (ethylenearenium) ions have been determined based on bromide transfer equilibria.The phenonium ion has been found to be stable even more than t-butyl cation, and the substituent effect on its stability has been analyzed based on the LArSR Eq., giving a ρ value of -17.5 and a r of 0.60.