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1,5-H shift

文献汇报. 1,5-H shift. 何玉萍 2010-11-06. R=CH3, X=- 45h yield 91% R=CH3, X=CH2 90h yield 95% R= OCH3 , X=- 20h yield 77% R= OCH3 , X=CH2 20h yield 90%. 其中类似 CF3 的强吸电子基团是必不可少的. 均不能发生类似的反应.

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1,5-H shift

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  1. 文献汇报 1,5-H shift 何玉萍 2010-11-06

  2. R=CH3, X=- 45h yield 91% R=CH3, X=CH2 90h yield 95% R=OCH3, X=- 20h yield 77% R=OCH3, X=CH2 20h yield 90% 其中类似CF3的强吸电子基团是必不可少的 均不能发生类似的反应 T.L., D. N. Reinhoudt, 24, 3923,1983.

  3. D. N. Reinhoudt 14% 66% X Lawesson reagent 1,R1=CH3, R2=CF3 2,R1=H, R2=H 3,R1=H, R2=CH3 4,R1=H, R2=C6H5 √ R2可以不必是强吸电子基团

  4. Mechanism Tetrahedron.1984,4309-4312

  5. D. N. Reinhoudt,JOC, 49, 2, 1984.

  6. Mechanism 总结: 1,溶剂效应(极性溶剂更容易促进反应) 2,lewis酸可以促进反应 3 4 任何可以稳定1,5-偶极的基团都可以促进反应 > > 与5不同

  7. D. N. Reinhoudt,Tetrahedron Letter, 1984, 25, 19, 2025.

  8. Synthesis, 2005, 2161. Synthesis, 2007, 2872.

  9. rt Daniel Seidel, Org. Lett. 2009, 11, 129.

  10. illustrate for the first time that such a reaction is amendable to enantioselective catalysis.

  11. the first example of a catalytic enantioselective hydride shift/ring closure reaction cascade Dainel Seidel, J. Am. Chem. Soc. 2009,131,13266

  12. the first example of a organocatalytic enantioselective hydride transfer/ring closure reaction cascade J. Am. Chem. Soc. DaeYoungKim, 2010, 132, 11847

  13. Daniel Seidel, J. Am. Chem. Soc. 2008, 130, 416

  14. 无杂原子 Sames, J. Am. Chem. Soc. 2005, 127, 12180.

  15. C-O 形成 1，BF3.Et2O是催化该反应最好的lewis acid 2，所得产物不一定全是螺环，如15，17. 但需要更强的lewis acid TiF4。 3， ketone 19也可以参与类似的反应。 只是还未找到更为有效的催化剂。 Sames, Org. Lett. 2005, 7, 5429.

  16. DFT caculation excellent yield No reaction Low yield

  17. Unactivated teminal alkynes Lewis acid activation of the terminal alkyne and the subsequent hydride transfer

  18. Greater hydride PtI4NoReation K2PtCl PtI4 more electrophilic and more accessible to the alkyne 苄醚 Sames, J. Am. Chem. Soc. 2009, 131, 16525.

  19. Deuterium Labeling Studies and Proposed Mechanisms [1,2]H

  20. less active need stronger activation Sames, Org. Lett. 2009, 11, 2972.

  21. the aryl alkyl ethers were less reactive in comparison to the dialkyl ethers no reaction was observed in the absence of catalyst under these conditions

  22. Akiyama, Org. Lett. 2010, 12, 1732.

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