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铜催化下羧酸炔丙酯在强碱作用下生成端基丙二烯的反应。另外在铜金属催化剂、多聚甲醛、高位阻2级胺(二环己胺、二异丙胺等)存在下,末端炔烃也可以得到端基丙二烯。
Crabbe联烯合成受限于多聚甲醛,其他醛不能生成联烯。2010年麻生明及其研究团队报道了新的合成方法,在廉价的的 ZnI2和吗啡啉存在下,由醛和端基炔合成了1,3-二取代联烯。
【Kuang, J.; Ma, S. J. Am. Chem. Soc. 2010, 132, 1786.】
反应机理
端基炔和多聚甲醛反应机理:
反应实例
Allene (3). To PhSCu (4.41 g, 25.5 mmol) in Et2O (100 mL) at 35 C was added 2.47 M BuLi in hexane (9.91 mL, 2.45 mmol). After 20 min at -30 C, 1 (2.26 g, 10.2 mmol) in Et2O (35 mL) was added dropwise at -78 C. After 1 h stirring, the mixture was quenched with 2 mL of sat NH4Cl at a rate of 0.16 mL/min. After 6 h at 78 C, the solids were filtered at r.t.. The organic phase after washing, evaporation and chromatography afforded 1.51 g of 3 (91%).
【Tet Lett., 1976, 2313】
【Tet Lett., 2008, 49,7230-7233】
【Journal of Organic Chemistry, 2012, 77, 7725-7729】
【Journal of Organic Chemistry, 2013, 78, 6890-6910】
【Tet Lett., 2013, 54,365-369】
相关文献
1 Crabbe´ P J Chem Soc Chem Comm 1976 183
2 Normant JF Tet Lett 1976 2313
3 Nantz MH Synthesis 1993 577
4 Hiemstra H J Org Chem 1997 62 8862
5 Takeda T Org Biomol Chem 2005 3 2914
6 Takahashi T J Org Chem 2005 70 8785
7 Crabbé, P.; Fillion, H.; André, D.; Luche, J.-L. J. Chem. Soc. Chem. Commun. 1979, 859.
8 Kuang, J.; Ma, S. J. Org. Chem. 2009, 74, 1763.
9 Kitagaki, S.; Komizu, M.; Mukai, C. Synlett 2011, 1129.
参考资料
一、Organic Syntheses Based On Name Reactions, 3RdEd, A. Hassner, Page 105.
二、化学空间:http://www.chem-station.com/cn/reactions/2015/05/crabbe%E8%81%94%E7%83%AF%E5%90%88%E6%88%90crabbe-allene-synthesis.html
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