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Palladium-catalyzed allylic amination

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  1. Palladium-catalyzed allylic amination

  2. Chem. Rev.1998, 98, 1689 Angew. Chem. Int. Ed.2008, 47, 4733

  3. Amination of Functionalized Alkenes Richard D. Connell et al. J. Org. Chem. 1988, 53, 3845 Bystorm S. E.et al. Tetrahedron Letters, 1985,26, 1749 Kuiling Ding, et al. J. Org. Chem. 2001, 66, 3238

  4. Chiral N-P Ligands Tamino Hayashi, et al, J. Am. Chem. Soc. 1989, 111, 6301 Togni, A. et al. J. Am. Chem. Soc. 1996, 118, 1031 Helmchen, G., et al.Tetrahedron: Asymmetry 1994, 5, 573.

  5. Trost, B. M. et al. J. Am. Chem. Soc. 1992, 114, 9327. Trost, B. M. et al. J. Am. Chem. Soc. 1994, 116, 4089. Trost, B. M. et al. J. Am. Chem. Soc. 1997, 119, 5962. Paul S. Pregosin, et al. Organometallics1999, 18, 1207

  6. Lixin Dai, Xuelong Hou, et al. J. Am. Chem. Soc.2001, 123, 7471

  7. Chiral P-S ligands Up to 98% ee Michael C. Willis, et al. Tetrahedron: Asymmetry , 2003, 14, 705; J. W. Faller, et al. Org. Lett., 2004, 6, 1301; J. W. Faller, et al. Org. Lett. 2005, 7, 633. Carlos CarreteroJ. Org. Chem. 2003, 68, 3679

  8. Chiral phosohine oxides Yasumasa Hamada, et al. J. Am. Chem. Soc.. 2004, 126, 3690 Yasumasa Hamada, et al. Org. Lett., 2007, 9, 927 Chatt, J.; Heaton, B. T. J. Chem. Soc. A 1968, 2745 Org. Lett., 2010, 12, 872

  9. Andrei Yudin Proticacid generated during the reaction is the prerequisite for product isomerization DBU keeps the reaction under kinetic control, but achieving a high b/l ratio requires greater discrimination between isomeric allyl palladium intermediates, which is achieved through ligand control. Giuliana Cardillo, et al. Org. Lett., 200810, 2425 J. Am. Chem. Soc. 2005, 127, 17516; J. Am. Chem. Soc.2004, 126, 5086; J. Am. Chem. Soc.2007, 129, 14172

  10. Aqueous Ammonia as Nucleophile Shu, Kobayashi. et al. J. Am. Chem. Soc. 2009, 131, 4200 Amination of Allylic Alcohols Shyh-Chyun Yang J. Org. Chem.1999, 64, 5000

  11. Kinetic Resolution of Indolines Xuelong Hou, et al. Org. Lett., 2009, 11, 1789

  12. Amination of Nonfunctionalized Alkenes Hegedus, L. S J. Am. Chem. Soc. 1978, 100, 5800 Stahl, S. S. Org. Lett. 2006, 8, 2257.

  13. Beccalli, E. M Beccalli, E. M. et al; J.Org. Chem. 2004, 69, 5627. Chem. Rev ,2007, 107 5318

  14. Christina M White Intramolecular Using this alternative palladium(II) source having a counterion that is a much weaker base, 1H NMR analysis at the same 2 h time point revealed predominant formation of a ð-allylPd complex (ca. 61%) and no significant formation of product 3a. The addition of an external acetate source to this ð-allylPd intermediateled to the formation of 3a with a similar yield and identicaldiastereoselectivity to that observed under standard catalytic conditions. Yields decrease over time,which was most likely due to formation of Pd-H in the oxidative aminopalladation pathway that mediates olefin isomerization to 2a J. AM. CHEM. SOC. 2007, 129, 7274 J. AM. CHEM. SOC. 2008, 130, 3316

  15. Intermaolecular Lewis acid activition Stoichiometric Studies To Evaluate the Role of (salen)CrCl2 The combination of Cr catalyst 2 with BQ was uniquely effective at promoting formation of aminated product 7 in 25% yield with regio- and stereoselectivities similar to those observed under standard catalytic conditions. Consistent with 2/BQ working together to promote functionalization,sterically hindered quinones such as 2,6-dimethyl quinone result in significantly diminished yieldsThese results suggest that Pd catalyst 1 mediates allylic C-H cleavage, while Cr catalyst 2 and BQ promote functionalization. J. AM. CHEM. SOC. 2008, 130, 3316

  16. Brønsted Base activition Lewis acid and Brønsted Base promoting intermolecular functionalization J. AM. CHEM. SOC. 2009, 131, 11701

  17. Theaminopalladation/-hydride elimination mechanism predicts formation of 22a-d2 but not 22b-d2. The observed formation of nearly equal amounts of products 22a-d2 and 22b-d2, however, argued against the possibility of aminopalladation/-hydride elimination pathway and in favor of a mechanism involving aπ-allyl-Pd intermediate. Org. Lett., 2009, 11, 2707 J. AM. CHEM. SOC. 2010, 132, 11978

  18. Conclusions: 1. All Pd(0)-catalyzed allylic aminations was promoted by chiral phosphines can not avoid regioselectivity directly. No other kinds of chiral organomoleculars was used. Most of them need additives and excess substrates(3 eq. of amines or even more) to prevent bypath product. 2. Most of Pd(ll)-catalyzed allylic aminations need additives to obtain product and high regioselectivity. Substrates were limited to functionalized amines.Consice mechanisms needed to be studied.