The metallation of Troeger's base

Tetrahedron Letters

Volumn 37, Issue 35, 1996, Pages 6267-6270

  Harmata, Michael ^a   Carter, Kevin W ^a   Jones, Darin E ^a   Kahraman, Mehmet ^a  

^a UNIVERSITY OF MISSOURI   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

PIPERAZINE DERIVATIVE; POLYCYCLIC AROMATIC COMPOUND;

ARTICLE; CHIRALITY; DRUG SYNTHESIS; NUCLEAR MAGNETIC RESONANCE; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0030603033     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/0040-4039(96)01392-5     Document Type: Article

References (21)

1. 1. (a) Vögtle, F. Fascinating Molecules in Organic Chemistry; Wiley: Chichester, 1992; pp 237-49.
2. (b) Bag, B.G. Curr. Sci. 1995, 68, 279.
3. 2. ur-Rahman, S. J. Chem. Soc. Pak. 1987, 9, 503.
4. 3. (a) However, its potential in asymmetric catalysis was acknowledged. See: Goldberg, Y.; Alper, H. Tetrahedron Lett. 1995, 36, 369.
5. (b) Minder, B.; Schuerch, M.; Mallat, T.; Baiker, A. Catal. Lett. 1995, 31, 143.
6. 4. For leading references, see: Harmata, M.; Murray, T. J. Org. Chem. 1989, 54, 3761.
7. 5. (a) Bag, B.G.; Maitra, U. Synth. Commun. 1995, 25, 1849.
8. (b) Sucholeiki, I.; Lynch, V.; Phan, L.; Wilcox, C.S. J. Org. Chem. 1988, 53, 98.
9. 6. (a) Metlesics, W.; Tavares, R.; Sternbach, L.H. J. Org. Chem. 1966, 31, 3356.
10. (b) Shenbor, M.I.; Smirnov, G.M. Vopr. Khim. Khim. Tekhnol. 1976, 43, 24; (CA 87:68019).
11. 7. (a) Analogues substituted on the bridging methylene are also known. For example, see: Johnson, R.A.; Gorman, R.R.; Wnuk, R.J.; Crittenden, N.J.; Aiken, J.W. J. Med. Chem. 1993, 36, 3202.
12. (b) Analogues in which a benzylic methylene and the bridging methylene are connected have been prepared. For example, see: Jircitano, A.J.; Sommerer, S.O.; Shelley, J.J. Acta Crystallogr., Sect. C 1994, C50, 445.
13. 8. Kessar, S.V. Singh, P.; Vohra, Kaur, N.P.; Singh, K.N. J. Chem. Soc., Chem. Commun. 1991, 568.
14. 9. Benzylic epimers of 3 are converted to 3 by treatment with sodium hydride, presumably the result of benzylic metallation, at least in an equilibrium sense. See reference 6a.
15. 1H NMR data of the reaction product suggested two compounds in a 1.7:1 ratio based on integration of peaks assigned to the methyl groups of both diastereomers. That the compounds were epimeric at the carbinol center was confirmed by oxidation, which led to a single ketone.
16. 11. (a) Wilen, S.H.; Qi, J.Z. J. Org. Chem. 1991, 56, 485.
17. (b) Maitra, U.; Bag, B.G.; Rao, P.; Powell, D. J. Chem. Soc. Perkin Trans. 1 1995, 2049.
18. 13C NMR) but in an unoptimized yield of only 18%.
19. 13. Seyden-Penne, J. Chiral Auxiliaries and Ligands in Asymmetric Synthesis; Wiley: New York, 1995.
20. 13C NMR and IR spectral data as well as satisfactory combustion analysis or high resolution exact mass data.
21. 4). Filtration and removal of solvent in vacuo gave crude product which was purified by flash chromatography.