Anionic ring-enlarging reaction of a hemiaminal system: Stereoselective approach to disubstituted tetrahydroisoquinolone

Synlett

Volumn , Issue 15, 2006, Pages 2449-2453

  Tomooka, Katsuhiko ^a   Tomoyasu, Takahiro ^a   Hanji, Takayuki ^a   Igawa, Kazunobu ^a  

^a TOKYO INSTITUTE OF TECHNOLOGY   (Japan)

Author keywords

aminocarbanion; Axial chirality; Hemiaminal; Stereoselective synthesis; Tetrahydroisoquinolone

Indexed keywords

PHTHALIMIDE DERIVATIVE; QUINOLONE DERIVATIVE;

ADDITION REACTION; ARTICLE; STEREOCHEMISTRY; SYNTHESIS;

EID: 33749325540     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-2006-950423     Document Type: Article

References (25)

1. (a) Chrzanowska, M.; Rozwadowska, M. D. Chem. Rev. 2004, 104, 3341.
2. (b) Briet, N.; Brookes, M. H.; Davenport, R. J.; Galvin, F. C. A.; Gilbert, P. J.; Mack, S. R.; Sabin, V. Tetrahedron 2002, 58, 5761.
3. For recent studies of the asymmetric synthesis of tetrahydroisoquinolones, see: (a) Vicario, J. L.; Badia, D.; Carrillo, L.; Anakabe, E. Tetrahedron: Asymmetry 2003, 14, 347.
4. (b) Derdau, V.; Snieckus, V. J. Org. Chem. 2001, 66, 1992.
5. (c) Davis, F. A.; Mohanty, P. K.; Burns, D. M.; Andemichael, Y. W. Org. Lett. 2000, 2, 3901.
6. (d) Davis, F. A.; Andemichael, Y. W. J. Org. Chem. 1999, 64, 8627.
7. (e) Clark, R. D.; Souchet, M.; Kern, J. R. J. Chem. Soc., Chem. Commun. 1989, 930.
8. (a) Tomoyasu, T.; Tomooka, K. Synlett 2004, 1925.
9. (b) Tomoyasu, T.; Tomooka, K.; Nakai, T. Tetrahedron Lett. 2003, 44, 1239.
10. (c) Tomoyasu, T.; Tomooka, K.; Nakai, T. Tetrahedron Lett. 2000, 41, 345.
11. (d) Tomoyasu, T.; Tomooka, K.; Nakai, T. Synlett 1998, 1147.
12. The ring-enlarging reaction of the phthalimide-derived enolate is well established as the Gabriel-Colman rearrangement; see: Allen, C. F. H. Chem. Rev. 1950, 47, 275.
13. 1H NMR analysis.
14. Bisagni and co-workers reported a similar tetrahydroisoquinolone synthesis involving the dilithiated intermediate, see: Delcey, M. C.; Huel, C.; Bisagni, E. Heterocycles 1995, 47, 1721.
15. The exact origin of the observed high reactivity of MeLi compared with that of n-BuLi is not clear at present, though it might be considered as the result of a difference of their aggregation states.
16. 4, filtered, and the solvent was removed under reduced pressure. Puri-fication by silica gel chromatography (hexane-EtOAc, 3:1) gave 56 mg (91%; dr 93%) of tetrahydroisoquinolone 5b.
17. The relative stereochemistry of 5c was determined as syn by X-ray crystallography of its dimethylated derivative 13 (Scheme 10). The stereochemistry of tetrahydroisoquinolones 5a, 5b, and 5d was speculated as syn based on its similarity with 5c. Crystallographic data for 13 have been deposited with the Cambridge Crystallographic Data Center as supplementary publication no. CCDC 610566. Copies of the data can be obtained free of charge on application to CCDC, 12 Union Road, Cambridge CB21EZ, UK (deposit @ccdc.cam.ac.uk).
18. Reviews on aza-Wittig rearrangement: (a) Tomooka, K. In The Chemistry of Organolithium Compounds; Rappoport, Z.; Marek, I., Eds.; John Wiley & Sons: New York, 2004, 749.
19. (b) Vogel, C. Synthesis 1997, 497.
20. Generation of the benzylic anion was confirmed by a trapping experiment using TMSCl.
21. DFT calculations were performed at the B3LYP/6-31+G(d) level with Gaussian 03 on TSUBAME system at Tokyo Institute of Technology. To simplify the calculation the possibility of the aggregation was not considered. The sum of electronic and zero-point energies was used as the energy values in Figure 2 and Scheme 7.
22. The enantiopurity of 3 was determined by HPLC analysis using a Sumichiral OA-3200 column.
23. It has been reported that the α-amino benzylic carbanion is stereochemically unstable; see: Hoffmann, R. W.; Ruhl, T.; Harbach, J. Liebigs Ann. Chem. 1992, 725.
24. 2C=CHMgBr provides (1R,′R)-isomer as the major epimer (dr = 83:17) and its stereochemistry was unambiguously determined by X-ray crystallography. The detailed result as well as a ring-enlarging reaction of a vinyl analogue will be reported elsewhere.
25. The absolute stereochemistry of 3 was speculated based on the reaction mechanism.