Carbocationic systems, the Yukawa—Tsuno

Carbocationic systems, the Yukawa—Tsuno relationship in, 32, 267 Carbocations, partitioning between addition of nucleophiles and deprotonation,... 

Substituent effects on the solvolysis rates of PhCMeClCMej in 80% (v/v) aqueous acetone at 45 °C, and 2-MeC6H4CMe(CMe3)02CC6H4N02-4 in 50% (v/v) aqueous ethanol at 75 °C have been treated with the Yukawa-Tsuno equation to give p = -4.28 and r = 0.91, and p = —2.78 and r = 0.70, respectively. " The reduction in r values from 1.00 for full conjugation was ascribed to deviation from coplanarity of the carbocationic centre and the benzyUc -system in the transition state. Gas-phase stabilities of the corresponding carbocations were also studied. 

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