Complex polycyclic lactams from pericyclic cascade reactions of Zincke aldehydes

Journal of the American Chemical Society

Volumn 131, Issue 22, 2009, Pages 7546-7547

  Steinhardt, Sarah E ^a   Vanderwal, Christopher D ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CASCADE REACTIONS; CHEMICAL EQUATIONS; DIELS-ALDER CYCLOADDITION; DIENOPHILES; ELECTROCYCLIC RINGS; HOMOALLYLIC AMINES; KEY REACTIONS; MECHANISTIC STUDIES; PYRIDINIUM SALTS; SECONDARY AMINES; SIGMATROPIC SHIFTS; THERMALLY INDUCED; UNSATURATED AMIDES;

ALDEHYDES; AMINATION; AMINES; FUNCTIONAL GROUPS; HYDROGEN; OLEFINS; REACTION KINETICS; STEREOSELECTIVITY; SYNTHESIS (CHEMICAL);

AMIDES;

ALDEHYDE; LACTAM; AMIDE; FURAN DERIVATIVE; POLYENE; PYRIDINE DERIVATIVE; PYRIDONE DERIVATIVE;

AMINOLYSIS; ARTICLE; CHEMICAL REACTION; CYCLOADDITION; DIELS ALDER REACTION; HEATING; REACTION TIME; STEREOCHEMISTRY; SYNTHESIS; TEMPERATURE; CHEMISTRY; CYCLIZATION;

ALDEHYDES; AMIDES; CYCLIZATION; FURANS; LACTAMS; POLYENES; PYRIDINES; PYRIDONES;

EID: 67650552613     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja902439f     Document Type: Article

References (19)

1. Steinhardt, S. E.; Silverston, J. S.; Vanderwal, C. D. J. Am. Chem. Soc. 2008, 130, 7560-7561.
2. For our other work with Zincke chemistry, see: (a) Kearney, A. M.; Vanderwal, C. D. Angew. Chem., Int. Ed. 2006, 45, 7803-7806.
3. (b) Michels, T. D.; Rhee, J. U.; Vanderwal, C. D. Org. Lett. 2008, 10, 4787-4790.
4. (c) Martin, D. B. C.; Vanderwal, C. D. J. Am. Chem. Soc. 2009, 131, 3472-3473.
5. (a) Zincke, T. Liebigs Ann. Chem. 1903, 330, 361-374.
6. (b) Zincke, T. Liebigs Ann. Chem. 1904, 333, 296-345.
7. (c) Zincke, T.; Wurker, W. Liebigs Ann. Chem. 1905, 338, 107-141.
8. (d) König, W. J. Prakt. Chem. 1904, 69, 105-137.
9. (a) Becher, J. Synthesis 1980, 589-612.
10. (b) Becher, J.; Finsen, L.; Winckelmann, I. Tetrahedron 1981, 37, 2375-2378.
11. (c) Cheng, W.-C.; Kurth, M. J. Org. Prep. Proced. Int. 2002, 34, 585-608.
12. Please see Supporting Information for details.
13. Except for 12e, the crude cycloadducts were formed in ≥10:1 dr.
14. For a review of the extensive use of furans as Diels-Alder dienes, see: Kappe, C. O.; Murphree, S. S.; Padwa, A. Tetrahedron 1997, 53, 14179-14233.
15. For examples of furans serving as dienophiles, see: Chen, C.-H.; Rao, P. D.; Liao, C.-C. J. Am. Chem. Soc. 1998, 120, 13254-13255, and references therein.
16. It is probable that the normal electron demand cycloaddition with furan serving as diene is operative here, but that the reversible nature of furan Diels-Alder reactions enables eventual formation of thermodynamic products 12f and 12g. Preliminary calculations that support this hypothesis can be found in the Supporting Information. It appears unlikely that a cycloaddition with furan serving as the diene followed by a [3,3]-sigmatropic rearrangement could account for the observed product; the stereospecificity of the Diels-Alder reaction of a Z-diene with the furan precludes formation of the stereoisomer of product that could undergo such a sigmatropic rearrangement.
17. For an important early discussion of this general mode of stereocontrol, see: Woodward, R. B.; Bader, F. E.; Bickel, H.; Frey, A. J.; Kierstead, R. W. Tetrahedron 1958, 2, 1-57.
18. For a related study that demonstrates an interesting solvent dependence on stereochemical outcome, see: Guy, A.; Lemaire, M.; Negre, M.; Guette, J. P. Tetrahedron Lett. 1985, 26, 3575-3578.
19. Another advantage of this method for in situ Z-diene synthesis is that the α- and β-substituted α,β,γ,δ-unsaturated amides generated in this way would be difficult to access so efficiently by other means.