Novel diastereo- and enantioselectivities in the chiral oxazaborolidinone-promoted asymmetric aldol reaction of highly hindered aldehydes having a quaternary carbon at α position and limitations observed on catalyst (promoter) control

Tetrahedron Letters

Volumn 39, Issue 45, 1998, Pages 8287-8290

  Kiyooka, Syun Ichi ^a   Maeda, Hirofumi ^a   Hena, Mostofa Abu ^a   Uchida, Mai ^a   Kim, Chul Sa ^a   Horiike, Michio ^a  

^a KOCHI UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

ALDEHYDE DERIVATIVE; OXAZABOROLIDINONE 1; OXAZABOROLIDINONE 2; UNCLASSIFIED DRUG;

ARTICLE; CATALYSIS; CHIRALITY; DIASTEREOISOMER; STEREOCHEMISTRY;

EID: 0032487769     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(98)01808-5     Document Type: Article

References (19)

1. (1) Enantioselective Acyclic Stereoselection Under Catalyst Control 4. For part 3; see Kiyooka, S. -i. ; Maeda, H. Tetrahedron: Asymmetry, 1997, 8, 3371-3374.
2. (2) (a) Gawley, R. E.; Aubé, J. Principles of Asymmetric Synthesis ; Pergamon, Oxford, 1996.
3. (b) Kiyooka, S. -i. Development of a Chiral Lewis Acid-Promoted Asymmetric Aldol Reaction Using Oxazaborolidinone, in Reviews on Heteroatom Chemistry, 1997, 17, 245-270. The catalyst as a term in this paper involves the meaning of a promoter used in stoichiometric amounts. The chiral oxazaborolidinones, 1 and 2, were used as a promoter in the reaction of bulkyl aldehydes although catalytic conditions are available for simple aldehydes by controlling the reaction conditions.
4. (3) (a) Kiyooka, S. -i.; Kira, H.; Hena, M. A. Tetrahedron Lett. 1996, 37, 2597-2600.
5. (b) Kiyooka, S. -i.; Yamaguchi, T; Maeda, H.; Kira, H.; Hena, M. A. Ibid. 1997, 38, 3553-3556.
6. (4) Kiyooka, S. -i.; Maeda, H. Tetrahedron: Asymmetry, 1997, 8, 3371-3374.
7. (5) (a) Evans, D. A.; Gauchet-Prunet, J. A.; Carreira, E. M.; Charette, A. B. J. Org. Chem. 1991, 56, 741-750.
8. (b) Corey, E. J.; Pan, B. -C.; Huo, D. H.; Deardrorff, D. R. J. Am. Chem. Soc. 1982, 104, 6816-6818.
9. (c) White, J. D.; Vedananda, T. R.; Kang, M.; Choudrhy, S. C. Ibid. 1986, 108, 8105-8107.
10. (d) Balog, A.; Meng, D.; Kamenecka, T.; Bertinato, P.; Su, D. -S.; Sorensen, E. J.; Danishefsky, S. J. Angew. Chem. Int. Ed. Engl. 1996, 35, 2801-2803.
11. (e) Yang, Z. ; He, Y.; Vourloumis, D.; Vallberg, H.; Nicolaou, K. C. Ibid. 1997, 36, 166-168.
12. (f) Schinzer, D.; Limberg, A.; Bauer, A.; Böhm, O. M.; Cordes, M. Ibid. 1997, 36, 523-524.
13. (6) Kiyooka, S. -i.; Kaneko, Y.; Kume, K. -i. Tetrahedron Lett. 1992, 34, 4927-4930.
14. (7) The structure of the syn-and anti-products was reconfirmed on the basis of NOE experiments of their acetonides derived from the aldol products.
15. (8) Corey, E. J.; Barnes-Seeman, D.; Lee, T. W. Tetrahedron Lett. 1997, 38, 4351-4354.
16. (9) Ishihara, K.; Maruyama, T.; Mori, M.; Gao, Q.; Furuta, K.; Yamamoto, H. Bull. Chem. Soc. Jpn. 1993, 66, 3483-3491.
17. (10) Gennari, C. Selectivities in Lewis Acid Promoted Reactions, Schinzer, D. Ed.: Kluwer Academic Publishers, Dordrecht, 1988; pp 53-71.
18. 3, 100 MHz): δ (ppm) -4.5, -4.3, 0.0, 13.8, 14.1, 14.2, 16.9, 18.12, 21.51, 22.7, 25.2, 26.0, 32.0, 35.6, 36.7, 41.7, 43.0, 60.3, 71.8, 77.7, 87.4, 126.4, 136.35, 176.8.
19. (12) The aldol reaction of the TBS-protected aldehyde no longer proceeds because of over steric bulkiness. The evidence supports the mechanistic explanation with Fig. 2.