Timeline for Rate of dehydration for butan-2-ol and butane-2,3-diol
Current License: CC BY-SA 4.0
6 events
| when toggle format | what | by | license | comment | |
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| Jul 21, 2020 at 20:26 | comment | added | Mathew Mahindaratne | @Andrew: The mechanism is similar to neopentyl alcohol elimination. Primary carbocation formation is assisted by concomitant shift of methide group. Nevertheless, the reaction is slow. | |
| Jul 21, 2020 at 20:18 | comment | added | Andrew | I just looked up the Emerson reference that you cited, and it also says the departure of H2O is generally believed to be rate-limiting, although it may be concerted with and aided by the hydride shift. Certainly, the hydride shift alone is not the RDS and would not "take more time and energy than a simple carbocation formation". In fact, concerted hydride shift would lower the reaction barrier by assisting the H2O elimination and leading directly to a more stable carbocation. | |
| Jul 21, 2020 at 18:40 | comment | added | Andrew | Why do you think hydride shift is RDS? All literature I have seen says it’s the cation formation that is rate-determining. It would be slower than 2-butanol because of electron withdrawing effect of second OH which destabilizes cation, apparently enough to overcome the statistical advantage of two OH groups. | |
| Jul 21, 2020 at 14:42 | vote | accept | Khushi Ladha | ||
| Jul 22, 2020 at 4:05 | |||||
| Jul 21, 2020 at 14:29 | history | edited | andselisk♦ | CC BY-SA 4.0 |
Corrected units symbols usage
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| Jul 21, 2020 at 14:06 | history | answered | Aniruddha Deb | CC BY-SA 4.0 |