Abstract
The iodine catalyzed isomerization of 2,3-dimethylbutene-1 (DMB-1) to 2,3-dimethyl-butene-2 (DMB-2) has been investigated over the temperature range 408 to 564 K. The equilibrium constants for this reaction, DMB-1 [equilibrium] DMB-2, have been measured as a function of temperature. These values and [bar over]ΔC°[subscript p] = -2.0 cal/K-mol leads to ΔH°[subscript r](486 K) = - 2.05 ± 0.04 kcal/mol and ΔS°[subscript r](486 K) = - 2.85 ± 0.09 cal/K-mol. These results are nominally independent of the heat capacity term. Using an estimated [bar over]ΔC°[subscript p] = 1.9 ± 1 cal/K-mol for 486 to 298 K, one calculated ΔH°[subscript r](298 K) = - 1.70 ± 0.2 kcal/mol and ΔS°[subscript r](298 K) = -1.93 ± 0.5 cal/K-mol. These results are compared and combined with previous data to derive: ΔH°[subscript f,298](DMB-2, g) = - 16.35 ± 0.35 kcal/mol and ΔH°[subscript f,298] (DMB-1, g) = - 14.65 ± 0.40 kcal/mol. ...
Wu, Mei-chia Rebekah (1971). The stabilization energies of methyl- and fluoro- substituted allylic radicals. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -444897.