The unusual role of CO transfer in molybdenum-catalyzed asymmetric alkylations

Journal of the American Chemical Society

Volumn 124, Issue 43, 2002, Pages 12656-12657

  Krska, Shane W ^a   Hughes, David L ^a   Reamer, Robert A ^a   Mathre, David J ^a   Sun, Yongkui ^a   Trost, Barry M ^b  

^a MERCK RESEARCH LABORATORIES   (United States)

^b STANFORD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CARBON MONOXIDE; MOLYBDENUM;

ALKYLATION; ARTICLE; CATALYST; CRYSTALLOGRAPHY; REACTION ANALYSIS; REACTION OPTIMIZATION; SPECTROSCOPY; STEREOCHEMISTRY; STOICHIOMETRY;

EID: 0037202197     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja028035h     Document Type: Article

References (20)

1. Trost, B. M.; Hachiya, I. J. Am. Chem. Soc. 1998, 120, 1104-1105; Trost, B. M.; Hildbrand, S.; Dogra, K. J. Am. Chem. Soc. 1999, 121, 10416-10417.
2. Trost, B. M.; Hachiya, I. J. Am. Chem. Soc. 1998, 120, 1104-1105; Trost, B. M.; Hildbrand, S.; Dogra, K. J. Am. Chem. Soc. 1999, 121, 10416-10417.
3. Lloyd-Jones, G. C.; Pfaltz, A. Angew. Chem., Int. Ed. Engl. 1995, 34, 462-464; Glorius, F.; Pfaltz, A. Org. Lett. 1999, 1, 141-144.
4. Lloyd-Jones, G. C.; Pfaltz, A. Angew. Chem., Int. Ed. Engl. 1995, 34, 462-464; Glorius, F.; Pfaltz, A. Org. Lett. 1999, 1, 141-144.
5. Belda, O.; Kaiser, N.-F.; Bremberg, U.; Larhed, M.; Hallberg, A.; Moberg, C. J. Org. Chem. 2000, 65, 5868-5870; Kaiser, N.-F.; Bremberg, U.; Larhed, M.; Moberg, C.; Hallberg, A. Angew. Chem., Int. Ed. 2000, 39, 3596-3598.
6. Belda, O.; Kaiser, N.-F.; Bremberg, U.; Larhed, M.; Hallberg, A.; Moberg, C. J. Org. Chem. 2000, 65, 5868-5870; Kaiser, N.-F.; Bremberg, U.; Larhed, M.; Moberg, C.; Hallberg, A. Angew. Chem., Int. Ed. 2000, 39, 3596-3598.
7. Malkov, A. V.; Spoor, P.; Vinader, V.; Kocovsky, P. Tetrahedron Lett. 2001, 42, 509-512; Kocovsky, P.; Malkov, A. V.; Vyskocil, S.; Lloyd-Jones, G. C. Pure Appl. Chem. 1999, 71, 1425-1433.
8. Malkov, A. V.; Spoor, P.; Vinader, V.; Kocovsky, P. Tetrahedron Lett. 2001, 42, 509-512; Kocovsky, P.; Malkov, A. V.; Vyskocil, S.; Lloyd-Jones, G. C. Pure Appl. Chem. 1999, 71, 1425-1433.
9. Trost, B. M.; Dogra, K.; Hachiya, I.; Emura, T.; Hughes, D. L.; Krska, S.; Reamer, R. A.; Palucki, M. P.; Yasuda, N.; Reider, P. J. Angew. Chem., Int. Ed. 2002, 41, 1929-1932.
10. 15N resonances of the pyridine and one of the amide nitrogens were shifted in complex 8 (δ 273, 133, respectively) relative to their values in free ligand 6 (δ 304, 118, respectively). The resonance of the unbound amide remained relatively unchanged (δ 123 in 8, vs 119 in 6).
11. 2) = 0.1555, GOF = 1.050. The THF solvent molecules were disordered.
12. Curtis, M. D.; Eisenstein, O. Organometallics 1984, 3, 887-895.
13. The X-ray crystal structure of a monomeric Mo allyl complex of 7 (Mo:7 = 2:1) has been reported: Morales, D.; Pérez, J.; Riera, L.; Riera, V.; Corzo-Suárez, R.; García-Granda, S.; Miguel, D. Organometallics 2002, 21, 1540-1545.
14. Complex 9 can exist in any of four possible isomers wherein the ligand binds in a facial, tridentate fashion in one of two geometries (defined by either A or A stereochemistry between the skew lines formed by the two CO ligands and the two bound N atoms of the chiral ligand) and the π-allyl fragment binds via its re or si face.
15. NMR characterization data for 9 were originally discussed in ref 5 and are included in the Supporting Information. The NOE data are consistent either with the structure shown in Figure 1 or with the diastereomeric structure formed by inversion of stereochemistry at both the metal center and the π-allyl fragment (cf. compound 20 in ref 5).
16. Deprotonation of ligand 7 is precedented in metal complexes: Mulqi, M.; Stephens, F. S.; Vag, R. S. Inorg. Chim. Acta 1981, 53, L91-L93; Adolfsson, H.; Moberg, C. Tetrahedron: Asymmetry 1995, 6, 2023-2031.
17. Deprotonation of ligand 7 is precedented in metal complexes: Mulqi, M.; Stephens, F. S.; Vag, R. S. Inorg. Chim. Acta 1981, 53, L91-L93; Adolfsson, H.; Moberg, C. Tetrahedron: Asymmetry 1995, 6, 2023-2031.
18. This result is in agreement with previous reactivity studies (ref 5) which showed that deprotonating ligand 7 before catalyst formation gives typical yields and enantioselectivities in the allylic alklyation reaction.
19. Hughes, D. L.; Palucki, M.; Yasuda, N.; Reamer, R. A.; Reider, P. J. J. Org. Chem. 2002, 67, 2762-2768.
20. Intramolecular attack via a ligated malonate would provide the observed stereochemistry. However. since complex 9 is coordinatively saturated, precomplexation of malonate seems unlikely.