Mechanistic Investigation Leads to a Synthetic Improvement in the Hydrolytic Kinetic Resolution of Terminal Epoxides

Journal of the American Chemical Society

Volumn 126, Issue 5, 2004, Pages 1360-1362

  Nielsen, Lars P C ^a   Stevenson, Christian P ^a   Blackmond, Donna G ^b   Jacobsen, Eric N ^a  

^a HARVARD UNIVERSITY   (United States)

^b UNIVERSITY OF HULL   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

1 HEXENE; ACETIC ACID; CHLORIDE; COBALT COMPLEX; EPOXIDE; LEWIS ACID; OXIDE;

ARTICLE; ASYMMETRIC CATALYSIS; CALORIMETRY; CATALYSIS; ENANTIOMER; HYDROLYSIS; MICHAELIS MENTEN KINETICS; OXIDATION; REPRODUCIBILITY; RING OPENING; SYNTHESIS;

COBALT; EPOXY COMPOUNDS; ETHYLENEDIAMINES; HYDROLYSIS; KINETICS; ORGANOMETALLIC COMPOUNDS;

EID: 1042265088     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja038590z     Document Type: Article

References (18)

1. (a) Tokunaga, M.; Larrow, J. F.; Kakiuchi, F.; Jacobsen, E. N. Science 1997, 277, 936-938.
2. (b) Schaus, S. E.; Brandes, B. D.; Larrow, J. F.; Tokunaga, M.; Hansen, K. B.; Gould, A. E.; Furrow, M. E.; Jacobsen, E. N. J. Am. Chem. Soc. 2002, 124, 1307-1315 and references therein.
3. (a) Hansen, K. B.; Leighton, J. L.; Jacobsen, E. N. J. Am. Chem. Soc. 1996, 118, 10924-10925.
4. (b) Jacobsen, E. N. Acc. Chem. Res. 2000, 33, 421-431.
5. This insight has been applied in a practical context to the development of covalently linked multimeric catalysts that display high reactivity as a result of cooperative intramolecular reactivity. See: (a) Ready, J. M.; Jacobsen, E. N. J. Am. Chem. Soc. 2001, 123, 2687-2688.
6. (b) Ready, J. M.; Jacobsen, E. N. Angew. Chem., Int. Ed. 2002, 41, 1374-1377.
7. (c) White, D. E.; Jacobsen, E. N. Tetrahedron: Asymmetry 2003, 14, 3633-3638.
8. (a) See footnote 24 in ref 1b.
9. (b) Kim, G.-J.; Lee, H.; Kim. S.-J. Tetrahedron Lett. 2003, 44, 5005-5008.
10. Ready, J. M.; Jacobsen, E. N. J. Am. Chem. Soc. 1999, 121, 6086-6087.
11. nBu): 2c (94% ee), 2d (83% ee), 2e (99% ee). The maximum amount of counterion addition product (X ≠ OH) is equal to the catalyst loading and therefore contributes minimally to epoxide conversion.
12. - complex could be initiated by addition of a noncoordinating Bronsted base such as 2,6-lutidine, presumably by deprotonation of coordinated water to generate 1b.
13. D was fixed at 0 for the purposes of kinetic modeling. See the Supporting Information for a detailed description of these experiments.
14. 2.
15. In addition to irreversible counterion addition, catalyst partitioning can also be controlled by converting Co-OH into Co-X by addition of HX. See the Supporting Information.
16. Because both the rate of counterion addition and the rate of the HKR depend on the concentration of Co-X, the catalyst partitioning near the end of the reaction is expected to vary at different catalyst loadings.
17. With all catalysts, 1-hexene oxide can be recovered in >99% ee and >40% yield based on racemic epoxide.
18. N1 pathways. For such substrates, less Lewis acidic catalysts such as la remain the most effective in the HKR. Schiffler, M. A., work in progress.