羟醛缩合反应(Aldol condensation)
用Zimmerman-Traxler六元环过渡态模型(J. Am. Chem. Soc. 1957, 79, 1920.)能够较好的解释说明底物与产物立体化学见得关系。因为醛的取代基equatorial处在平伏位置的过渡态稳定,有烯醇的立体特异性决定产物的立体化学。也就是说,由Z-烯醇盐得到syn构型羟醛产物、由E-烯醇盐得到anti构型产物。
一般而言,使用M-O键强的金属(硬酸,络合能较大的金属)六元环过渡态的环足够稳固,立体选择性会提高。加入HMPA等与锂等金属配位能力较强的配位性溶剂、可使金属烯醇盐得到极化,提高反应性能。另一方面,因它不可能采取六元环过渡态,会使选择性反转,就变得依赖于底物。
反应实例
【Tetrahedron 1997, 53, 9169-9202】
【J. Org. Chem. 2002, 67, 7750-7760】
【Org. Lett. 2003, 5, 733-736】
【Tetrahedron Lett. 1980, 21, 1031-1034】
【Angew. Chem. Int. Ed. 1997, 36, 166-168】
【J. Org. Chem. 2006,5228-5230】
【Eur. J. Org. Chem. 2008, 1759-1766】
【Angew. Chem. Int. Ed. 2008, 47, 6877-6880】
【Org. Lett. 2012, 14, 178-181】
1. Wurtz, C. A. Bull. Soc. Chim. Fr. 1872, 17, 436-442. Charles Adolphe Wurtz (1817-1884) was born in Strasbourg, France. After his doctoral training, he spent a year under Liebig in 1843. In 1874, Wurtz became the Chair of Organic Chemistry at the Sorbonne, where he educated many illustrous chemists such as Crafts, Fittig, Friedel, and van’t Hoff. The Wurtz reaction, where two alkyl halides are treated with sodium to form a new carbon-carbon bond, is no longer considered synthetically useful, although the aldol reaction that Wurtz discovered in 1872 has become a staple in organic synthesis. Alexander P. Borodin is also credited with the discovery of the aldol reaction together with Wurtz. In 1872 he announced to the Russian Chemical Society the discovery of a new by-product in aldehyde reactions with properties like that of an alcohol, and he noted similarities with compounds already discussed in publications by Wurtz from the same year.
2. Nielsen, A. T.; Houlihan, W. J. Org. React. 1968, 16, 1-438. (Review).
3. Still, W. C.; McDonald, J. H., III. Tetrahedron Lett. 1980, 21, 1031-1034.
4. Mukaiyama, T. Org. React. 1982, 28, 203-331. (Review).
5. Mukaiyama, T.; Kobayashi, S. Org. React. 1994, 46, 1-103. (Review on tin(II) enolates).
6. Johnson, J. S.; Evans, D. A. Acc. Chem. Res. 2000, 33, 325-335. (Review).
7. Denmark, S. E.; Stavenger, R. A. Acc. Chem. Res. 2000, 33, 432-440. (Review).
8. Yang, Z.; He, Y.; Vourloumis, D.; Vallberg, H.; Nicolaou, K. C. Angew. Chem. Int. Ed. 1997, 36, 166-168.
9. Mahrwald, R. (ed.) Modern Aldol Reactions, Wiley-VCH: Weinheim, Germany, 2004. (Book).
10. Desimoni, G.; Faita, G.; Piccinini, F.; Toscanini, M. Eur. J. Org. Chem. 2006,5228-5230.
11. Guillena, G.; Najera, C.; Ramon, D. J. Tetrahedron: Asymmetry 2007, 18, 2249-2293. (Review on enantioselective direct aldol reaction using organocatalysis.)
12. Doherty, S.; Knight, J. G.; McRae, A.; Harrington, R. W.; Clegg, W. Eur. J. Org. Chem. 2008, 1759-1766.
13. O’Brien, E. M.; Morgan, B. J.; Kozlowski, M. C. Angew. Chem. Int. Ed. 2008, 47, 6877-6880.
14. Trost, B. M.; Brindle, C. S. Chem. Soc. Rev. 2010, 39, 1600-1632. (Review).
15. Gazaille, J. A.; Abramite, J. A.; Sammakia, T. Org. Lett. 2012, 14, 178-181.
16. Esumi, T.; Yamamoto, C.; Tsugawa, Y.; Toyota, M.; Asakawa, Y.; Fukuyama Y. Org. Lett. 2013, 15, 1898–1901.
编辑自:
一、Name Reactions (A Collection of Detailed Reaction Mechanisms), Jie Jack Li, Aldol condensation,page 3-5.
二、Strategic Applications of Named Reactions in OrganicSynthesis, László Kürti and Barbara Czakó, aldol reaction, page 8-9.
三、化学空间:https://cn.chem-station.com/reactions/%E5%8A%A0%E6%88%90%E5%8F%8D%E5%BA%94/2014/05/%E4%BA%A4%E5%8F%89%E7%BE%9F%E9%86%9B%E7%BC%A9%E5%90%88%E5%8F%8D%E5%BA%94cross-aldol-reaction.html
相关反应