Stereoselective one-pot synthesis of β-lactams by reaction of 2-pyridylthioesters with imines in the presence of AlBr3 or EtAlCl2

Tetrahedron

Volumn 52, Issue 7, 1996, Pages 2583-2590

  Annunziata, Rita ^a   Benaglia, Maurizio ^a   Cinquini, Mauro ^a   Cozzi, Franco ^a   Martini, Oscar ^a   Molteni, Valentina ^a  

^a CNR   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

BETA LACTAM DERIVATIVE;

ARTICLE; DRUG SYNTHESIS; NUCLEAR MAGNETIC RESONANCE; PRIORITY JOURNAL; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0030023388     PISSN: 00404020     EISSN: None     Source Type: Journal    
DOI: 10.1016/0040-4020(95)01087-4     Document Type: Article

References (38)

1. a) Cinquini, M.; Cozzi, F.; Cozzi, P.G.; Consolandi, E. Tetrahedron 1991, 47, 8767.
2. b) Annunziata, R.; Cinquini, M.; Cozzi, F.; Cozzi, P.G. J. Org. Chem. 1992, 57, 4155.
3. c) Annunziata, R.; Cinquini, M.; Cozzi, F.; Lombardi Borgia, A. Gazz. Chim. Ital. 1993, 123, 181.
4. d) Annunziata, R.; Benaglia, M.; Cinquini, M.; Cozzi, F.; Ponzini, F. J. Org. Chem. 1993, 58, 4746.
5. e) Annunziata, R.; Benaglia, M.; Cinquini, M.; Cozzi, F.; Ponzini, F.; Raimondi, L. Tetrahedron 1994, 50, 2939.
6. f) Annunziata, R.; Benaglia, M.; Cinquini, M.; Cozzi, F.; Raimondi, L. Tetrahedron 1994, 50, 9471.
7. g) Annunziata, R.; Benaglia, M.; Chiovato, A.; Cinquini, M.; Cozzi, F. Tetrahedron 1995, 51, 10025. This method of preparation of trichlorotitanium enolates was originally reported by Evans, et al. for ketones and 2-oxazolidinones, as described in: Evans, D.A.; Bilodeau, M.T.; Somers, T.C.; Clardy, J.; Cherry, D.; Kato, Y. J. Org. Chem. 1991, 56, 5750, and references therein.
8. g) Annunziata, R.; Benaglia, M.; Chiovato, A.; Cinquini, M.; Cozzi, F. Tetrahedron 1995, 51, 10025. This method of preparation of trichlorotitanium enolates was originally reported by Evans, et al. for ketones and 2-oxazolidinones, as described in: Evans, D.A.; Bilodeau, M.T.; Somers, T.C.; Clardy, J.; Cherry, D.; Kato, Y. J. Org. Chem. 1991, 56, 5750, and references therein.
9. Annunziata, R.; Benaglia, M.; Cinquini, M.; Cozzi, F.; Raimondi, L. Tetrahedron 1994, 50, 5821.
10. a) Annunziata, R.; Benaglia, M.; Cinquini, M.; Cozzi, F. Tetrahedron Lett. 1995, 36, 613.
11. b) Annunziata, R.; Benaglia, M.; Cinquini, M.; Cozzi, F.; Molteni, V. Tetrahedron 1995, 51, 8941.
12. Reviews: (a) Hart, D.J.; Ha, D.-C. Chem. Rev. 1989, 89, 1447.
13. b) Brown, M.J. Heterocycles 1989, 29, 2225.
14. c) van der Steen, F.H.; van Koten, G. Tetrahedron 1991, 47, 7503.
15. 2AlCl at -70°C: Wada, M.; Aiura, H.; Akiba, K. Tetrahedron Lett. 1987, 28, 3377.
16. 2AlCl was too weak as LA to promote the reaction.
17. 1H NMR analysis of the crude reaction mixtures. The assignment resided on the value of the β-lactam HC-3/HC-4 coupling constant (J trans = 2.0-2.5 Hz; J cis = 5.0-6.0 Hz).
18. 2: 2.75, 3.00, 3.10; HC-3 (of pyridine): 7.63, 7.90, 7.61; HC-4: 7.80, 8.50, 8.19; HC-5: 7.33, 8.05, undetermined; HC-6: 8.61, 8.90, 8.21. Aluminum LA are known to have a maximum co-ordination number of four: Lehmkuhl, H. Angew. Chem. Int. Ed. Engl. 1964, 3, 107.
19. 2 signal.
20. 3N was necessary for the reaction to occur in good yields.
21. Cyclic models are used to rationalize β-lactam formation by the condensation of imines with metal enolate in general (see ref. 4), and with 2-pyridylthioester enolate in particular (see ref. 1-3).
22. Imines of aromatic aldehydes are known to exist and react in the (E) configuration, while those of aliphatic aldehydes generally exist as mixtures of (E) and (Z) isomers. For a review see: McCarty, C.G. in: "The Chemistry of the C-N Double Bond", Patai, S.; Ed.; Interscience, New York, 1970; chapter 9, pp 363-464. Aromatic imines such as 2 and 8 were shown not to isomerize even in the presence of strong LA (see ref. 1 and 3).
23. For a discussion of N-acyliminium ion formation by reaction of an activated carbonyl compound with imines see: Georg, G. I.; Ravikumar, V. T. in "The Organic Chemistry of β-Lactams", Georg, G. I., Ed.; VCH, New York, 1993, Chapter 6, pp 295-368.
24. For the acid/base properties of 2-pyridylthiol see: a) Albert, A.; Barlin, G. B. J. Chem. Soc. 1959, 2384.
25. b) Jones, R. A.; Katrizky, A. R. J. Chem. Soc. 1958, 3610.
26. For a discussion of the basic nature of the imine nitrogen see: a) Weinstein, J.; McIninch, E. J. Am. Chem. Soc. 1960, 82, 6064.
27. b) Cordes, E. H.; Jencks, W. P. J. Am. Chem. Soc. 1962, 84, 832.
28. For a review see: Smith, J. W. in: "The Chemistry of the C-N Double Bond", Patai, S.; Ed.; Interscience, New York, 1970; chapter 5, pp 235-253.
29. Ketene formation can be ruled out since the unreacted 2-pyridylthioesters can be recovered from the reaction mixture.
30. 3+2 mixture.
31. Similar results were obtained by : Olah, G.A.; Kreienbuhl, P. J. Am. Chem. Soc. 1967, 89, 4756.
32. 3 mixture does not afford any β-lactam upon standing overnight at room temperature. This confirms the necessity of a base to ensure proton abstraction from adduct 26, and support the hypothesis that is the 2-pyridylthiolate ion that acts as a base in our reaction.
33. 4. See: Childs, R. F.; Mulholland, D. L.; Nixon, A. Can. J. Chem. 1982, 60, 801. See also: Laszlo, P.; Teston, M. J. Am. Chem. Soc. 1990, 112, 8750.
34. 4. See: Childs, R. F.; Mulholland, D. L.; Nixon, A. Can. J. Chem. 1982, 60, 801. See also: Laszlo, P.; Teston, M. J. Am. Chem. Soc. 1990, 112, 8750.
35. 3N (unpublished results from these laboratories).
36. 3 or EtAlCl2 as activators and N-methylephedrine as base or chiral LA ligand (see ref. 3a,b). Racemic products were obtained in these reactions.
37. Hirai, K.; Homma, H.; Mikoshiba, I. Heterocycles 1994, 38, 281.
38. Annunziata, R.; Cinquini, M.; Cozzi, F.; Molteni, V.; Schupp, O. Tetrahedron, submitted.