在Ti催化下格氏试剂和烯烃或炔烃进行交换得到新的格氏试剂，再和一些亲电试剂（氧气，二氧化碳，醛，腈等等）进行格氏反应。端基硅保护的炔丙醇和腈发生此反应可以制备各种取代呋喃。

反应机理

反应实例

β-(Cyclohexenyl)ethanol (3). To 1, prepared from Mg (13.2 g) and PrBr (61.3 g) in Et2O (150 mL), was added 2 (54 g, 0.5 mol) followed by TiCl4 (1 mL). After 2 h reflux and heating with more TiCl4 (0.5 mL), the mixture was oxidized with air and distilled to give 25 g of 3 (40%), bp 92–94 ℃.

【Cooper GD, Finkbeiner HL,  J Org Chem.,  1962, 27, 3395】

3-Trimethylsilyl-2-ethylfuran (6). Cp2TiCl2 (0.12 g, 0.48 mol) was added to i-BuMgBr in Et2O (43 mL, 0.4 M) under Ar at 0℃. 4 (0.18 g, 6.8 mmol) was added and the mixture was stirred for 6 h at r.t. EtCN (0.48 g, 8.8 mmol) was added and all was stirred for another 2 h at r.t. Workup and chromatography (silica gel) afforded 0.94 g of 6 (82%).

【Sato F, Tet Lett., 1984, 25, 5063】

【Tet Lett., 1993, 34, 4975-4978】

相关文献

1 Cooper GD, Finkbeiner HL J Org Chem 1962 27 3395

2 Sato F J Chem Soc Chem Comm 1981 718

3 Sato F Tet Lett 1983 24 1804

4 Sato F J Chem Soc Chem Comm 1983 162

5 Sato F Tet Lett 1984 25 5063

6 Adam W Synthesis 1994 567

7 Wolan A Tetrahedron 2010 66 15

参考文献

一、Organic Syntheses Based On Name Reactions, 3RdEd, A. Hassner, Page 96.

二、Reactionflash APP