Nickel-catalyzed asymmetric Negishi cross-couplings of secondary allylic chlorides with alkylzincs

Journal of the American Chemical Society

Volumn 130, Issue 9, 2008, Pages 2756-2757

  Son, Sunghee ^a   Fu, Gregory C ^a  

^a MASSACHUSETTS INSTITUTE OF TECHNOLOGY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ALKYL GROUP; ALLYL CHLORIDE; NICKEL; ZINC DERIVATIVE;

ARTICLE; ASYMMETRIC CATALYSIS; CATALYST; CHEMICAL REACTION; CROSS COUPLING REACTION; ENANTIOSELECTIVITY; REACTION ANALYSIS;

ALKENES; ALKYLATION; CATALYSIS; HYDROCARBONS, CHLORINATED; LACTAMS; MOLECULAR STRUCTURE; NICKEL; ORGANOMETALLIC COMPOUNDS; STEREOISOMERISM; ZINC;

EID: 40949123444     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja800103z     Document Type: Article

References (23)

1. For reviews, see: (a) Pfaltz, A.; Lautens, M. In Comprehensive Asymmetric Catalysis; Jacobsen, E. N., Pfaltz, A., Yamamoto, H., Eds.; Springer: New York, 1999; Vol. 2, Chapter 24.
2. (b) Trost, B. M.; Van Vranken, D. L. Chem. Rev. 1996, 96, 395-422.
3. See also: Kar, A.; Argade, N. P. Synthesis 2005, 2995-3022.
4. For reviews, see: (a) Alexakis, A.; Malan, C.; Lea, L.; Tissot-Croset, K.; Polet, D.; Falciola, C. Chimia 2006, 60, 124-130.
5. (b) Yorimitsu, H.; Oshima, K. Angew. Chem., Int. Ed. 2005, 44, 4435-4439. Studies to date have focused largely on couplings of primary allylic electrophiles that generate terminal olefins (or, symmetrical secondary electrophiles).
6. For reactions with organozinc reagents, use of RZnX has been reported to be problematic (for example, see: Dübner, F.; Knochel, P. Angew. Chem., Int. Ed. 1999, 38, 379-381
7. 2 (e.g., 2-6 equiv) is typically employed, resulting in the transfer of ≤25% of the available R groups.
8. For example, see: (a) Consiglio, G.; Morandini, F.; Piccolo, O. J. Chem. Soc., Chem. Commun. 1983, 112-114.
9. (b) Gomez-Bengoa, E.; Heron, N. M.; Didiuk, M. T.; Luchaco, C. A.; Hoveyda, A. H. J. Am. Chem. Soc. 1998, 120, 7649-7650.
10. Progress with nucleophiles that exhibit greater functional-group tolerance has been relatively modest. For examples, see: (a) Chung, K.-G.; Miyake, Y.; Uemura, S. J. Chem. Soc., Perkin Trans. 1 2000, 15-18.
11. (b) Chen, H.; Deng, M.-Z. J. Organomet. Chem. 2000, 603, 189-193.
12. (c) Novak, A.; Fryatt, R.; Woodward, S. C. R. Chim. 2007, 10, 206-212.
13. Huo, S. Org. Lett. 2003, 5, 423-425.
14. (a) Fischer, C.; Fu, G. C. J. Am. Chem. Soc. 2005, 127, 4594-4595.
15. (b) Arp, F. O.; Fu, G. C. J. Am. Chem. Soc. 2005, 127, 10482-10483.
16. The addition of NaCl has a pronounced effect on the rate of the cross-coupling, but little impact on the ee. Two of the possible roles of NaCl are to increase the ionic strength of the reaction mixture (the use of more polar solvents is generally advantageous) and to activate the organozinc reagent. For a review of halide effects in transition-metal catalysis, see: Fagnou, K.; Lautens, M. Angew. Chem., Int. Ed. 2002, 41, 26-47.
17. 2-Pybox can be prepared in two steps from homophenylalanine. Under otherwise identical conditions, commercially available i-Pr-Pybox furnishes 78% ee and 92% yield.
18. 2 is bulky (eq 1), coupling is inefficient.
19. (b) For each Negishi reaction, the product is generated with >20:1 E:Z selectivity.
20. N2′ substitution (see ref 2).
21. 1 = aryl, Table 2) allylic chlorides can be achieved in excellent ee and moderate yield (≥94% ee; see the Supporting Information).
22. For applications of enantioselective metal-catalyzed allylations in total synthesis, see: Trost, B. M.; Crawley, M. L. Chem. Rev. 2003, 103, 2921-2943.
23. Suh, Y.-G.; Kim, S.-A.; Jung, J.-K.; Shin, D.-Y.; Min, K.-H.; Koo, B.-A.; Kim, H.-S. Angew. Chem., Int. Ed. 1999, 38, 3545-3547.