這主要是因為生成烯烴的穩(wěn)定性不同:
https://www.masterorganicchemistry.com
但按理說更多的取代基造成臨近的基團互相排斥,不是應該不穩(wěn)定?超共軛效應是造成這種烯烴穩(wěn)定性差異的主要原因之一,更多的取代基能提供更多超共軛的機會使電子離域(如下圖示):
影響因素
一、離去基團
二、取代基
反應實例
參考文獻
1. Aleksandr Mikhailovich Zaitsev (sometimes spelled as Saytseff, 1841–1910), like Markovnikov, was also a protégé of Aleksandr Mikhailovich Butlerov (1828–1882). But unlike Markovnikov’s lack of tact and inability to compromise with administrators, Zaitsev was a skilled politician. He held the position of chair at Kazan’ University for over four decades and educated a generation of organic chemistry.
2. Brown, H. C.; Wheeler, O. H. J. Am. Chem. Soc. 1956, 78, 2199–2210.
3. Chamberlin, A. R.; Bond, F. T. Synthesis 1979, 44–45.
4. Elrod, D. W.; Maggiora, G. M.; Trenary, R. G. Tetrahedron Comput. Methodol. 1990, 3, 163–174.
5. Larsen, N. W.; Pedersen, T. J. Mol. Spectrosc. 1994, 166, 372–382.
6. Reinecke, M. G.; Smith, W. B. J. Chem. Educ. 1995, 72, 541.
7. Guan, H.-P.; Ksebati, M. B.; Kern, E. R.; Zemlicka, J. J. Org. Chem. 2000, 65, 5177–5184.
8. Guan, H.-P.; Ksebati, M. B.; Kern, E. R.; Zemlicka, J. J. Org. Chem. 2000, 65, 5177-5184.
9. Hagen, T. J. Zaitsev Elimination, In Name Reactions for Functional Group Transformations; Li, J. J., Ed.; Wiley: Hoboken, NJ, 2007, pp 414-421. (Review).
10. Ramos, D. R.; Castillo, R.; Canle L., M.; Garcia, M. V.; Andres, J.; Santaballa, J. A. Org. Biomol. Chem. 2009, 7, 1807–1814. (Mechanism).
一、編譯自:Name Reactions (A Collection of Detailed Reaction Mechanisms), Jie Jack Li, Zaitsev’s elimination rule,page 650-651.