铜盐作用下,吡啶和苄基卤代物反应得到2位或4位苄基化产物的反应。其他的一些烷基卤代物也可以进行此反应,但产率不高。
反应机理
铜盐催化下的自由基机理
反应操作
Benzylpyridines (3) and (4). Pyr hydrochloride 1 (462 g, 4 mol), CuCl2 (5 g, 37 mmol) and Pyr (60 mL) were treated with benzyl chloride 2 (126.5 g, 115 mL, 1 mol) and refluxed for 12 h. The mixture was distilled until the temperature reached 195 C. The cooled residue was treated with water (200 mL) and 32% HCl (15 mL), stirred until homogeneous and made alkaline with 25% NH4OH.
Extraction with PE: PhH, washing the extract with NH4OH and evaporation afforded a mixture of 3 and 4, bp 123–125 ℃ and 175–190 ℃.
【Croock KE, J Am Chem Soc., 1948, 70, 416】
相关文献
1 Ladenburg A Liebig’s Ann 1883 16 1410
2 Croock KE J Am Chem Soc 1948 70 416
3R Brewster JH Org React 1953 7 135
4 Yoh SD J Phy Org Chem 2001 14 123
5 Radix S Tet Lett 2009 50 1828
6 Ackermann L Org Lett 2009 11 4966
编译自:Organic Syntheses Based On Name Reactions, 3RdEd, A. Hassner, Page 279.