| Autor: |
Tsuno, Yuho, Kusuyama, Yoshiaki, Sawada, Masami, Fujii, Takahiro, Yukawa, Yasuhide |
| Zdroj: |
Bulletin of the Chemical Society of Japan; November 1975, Vol. 48 Issue: 11 p3337-3346, 10p |
| Abstrakt: |
The rates of solvolysis of twenty-two m- and p-substituted a-methylbenzyl chlorides were determined in 80% aqueous acetone. The relative rates at 45 °C are not correlated linearly with s0or s. The use of Brown’s s+improves the fit but the resulting correlation is still concave. An excellent correlation, logk/k0=-4.950(s0+1.147?\barsR+), was obtained by applying the LArSR equation. The rvalue 1.15 suggests that the p-electronic contribution relative to the inductive contribution of -Rparasubstituents at the transition states differs with reaction, and is more important in the present a-methylbenzyl than Brown’s t-cumyl solvolysis (r=1.00 by definition). A set of ?\bars+and s+corresponding to the substituent constants for unit rwere calculated. The calculated s+values are in precise agreement with Brown’s primary s+values. The generality of the LArSR equation and some new substituent constants are illustrated. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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