An efficient catalytic deprotection of thioacetals employing bismuth triflate: Synthesis of pyrrolo[2,1-c] [1,4] benzodiazepines

Tetrahedron Letters

Volumn 44, Issue 14, 2003, Pages 2857-2860

  Kamal, Ahmed ^a   Reddy, P S M M ^a   Reddy, D Rajasekhar ^a  

^a INDIAN INSTITUTE OF CHEMICAL TECHNOLOGY   (India)

Author keywords

[No Author keywords available]

Indexed keywords

ACETAL DERIVATIVE; BENZODIAZEPINE DERIVATIVE; BISMUTH DERIVATIVE; BISMUTH TRIFLATE; DIMER; UNCLASSIFIED DRUG;

ARTICLE; CATALYSIS; CYCLIZATION; DEPROTECTION REACTION; DRUG SYNTHESIS; REDUCTION; ROOM TEMPERATURE; THIN LAYER CHROMATOGRAPHY;

EID: 0037474604     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(03)00437-4     Document Type: Article

References (31)

1. Green T.W., Wuts P.G.M. Protective Groups in Organic Synthesis. 3rd ed. 1999;John Wiley and Sons, New York.
2. Hanson J.R. Protecting Groups in Organic Synthesis. 1st ed. 1999;Blackwell Science, Malden, MA.
3. Kocienski P.J. Protecting Groups. 1st ed. 1994;George Thieme Verlag, Stuttgart.
4. p-TsOH/acetone: Colvin E.W., Raphael R.A., Roberts J.S. J. Chem. Soc., Chem. Commun. 1971;858.
5. Amberlyst-15/aqueous acetone: Coppola G.M. Synthesis. 1:1984;1021.
6. 2O: Ellision R.A., Lukenbach E.R., Chiu C.W. Tetrahedron Lett. 1975;499.
7. Aqueous DMSO: Kametani T., Kondoh H., Honda T., Suzuki Y., Mori W. Chem. Lett. 1989;901.
8. 4: Lipshutz B.H., Harvey D.F. Synth. Commun. 12:1982;267.
9. Fieser, L. F.; Fieser, M. Reagents for Organic Synthesis; John Wiley and Sons: New York, 1967; Vol. 1, p. 654; 1969; Vol. 2, p. 182.
10. Corey E.J., Erickson B.W. J. Org. Chem. 36:1971;3553.
11. Vedejs E., Fuchs P.L. J. Org. Chem. 36:1971;366.
12. Ho T.L., Ho H.C., Wong C.M. J. Chem. Soc., Chem. Commun. 1972;791.
13. Hirano A., Ukawa K., Yakabe S., Clark J.H., Morimoto T. Synthesis. 1997;858.
14. Schmittel M., Levis M. Synlett. 1996;315.
15. Komatsu N., Taniguchi A., Uda M., Suzuki H. Chem. Commun. 15:1996;1847.
16. Oishi T., Kamemoto K., Ban Y. Tetrahedron Lett. 13:1972;1085.
17. Fetizon M., Jurion M. J. Chem. Soc., Chem. Commun. 1972;382.
18. Mehta G., Uma R. Tetrahedron Lett. 37:1996;1897.
19. Kamal A., Laxman E., Reddy P.S.M.M. Synlett. 2000;1476.
20. Reglinski J. Norman N.C. Chemistry of Arsenic, Antimony and Bismuth. 1998;403-440 Blackie Academic and Professional, New York.
21. (a) Marshall J.A. Chemtracts. 1997, 249; (b) Organobismuth Chemistry; Suzuki, H.; Ikegami, T.; Matano, Y., Eds.; Elsevier: Amsterdam, 2001.
22. (a) Marshall J.A. Chemtracts. 1997, 249; (b) Organobismuth Chemistry; Suzuki, H.; Ikegami, T.; Matano, Y., Eds.; Elsevier: Amsterdam, 2001.
23. Labrouillere M., Le Roux A., Gaspard H., Laporterie A., Dubac J., Desmurs J.R. Tetrahedron Lett. 40:1999;285.
24. Repichet S., Zwick A., Vendier L., Le Roux C., Dubac J. Tetrahedron Lett. 43:2002;993.
25. Kamal A., Ramesh G., Laxman N., Ramulu P., Srinivas O., Neelima K., Kondapi A.K., Sreenu V.B., Nagarajaram H.A. J. Med. Chem. 45:2002;4679.
26. Gregson S.J., Howard P.W., Hartely J.A., Brooks N.A., Adams L.J., Jenkins T.C., Kelland L.R., Thurston D.E. J. Med. Chem. 44:2001;737.
27. Kamal A., Rao M.V., Laxman N., Ramesh G., Reddy G.S.K. Curr. Med. Chem. - Anti-cancer Agents. 2:2002;215.
28. Thurston D.E., Bose D.S. Chem. Rev. 94:1994;433. and references cited therein.
29. Thurston D.E., Bose D.S., Thompson A.S., Howard P.W., Leoni A., Croker S.J., Jenkins T.C., Neidle S., Hartley J.A., Hurley L.H. J. Org. Chem. 61:1996;8147.
30. Preparation of compound 6: To a stirred solution of 1,3-dibromopropane (101 mg, 1.0 mmol) in dry acetone (30 ml) was added anhydrous potassium carbonate (410 mg, 3 equiv.) and the monomer 3 (400 mg, 1 mmol). The reaction mixture was refluxed for 36-48 h. After completion of the reaction as indicated by TLC, potassium carbonate was removed by filtration and the filtrate was evaporated under reduced pressure. The residue was purified by column chromatography using ethyl acetate-hexane (7:3) as eluent to afford pure PBD dimer (n=3) in 93% yield.
31. 3): δ 2.01-2.17 (m, 2H), 2.27-2.44 (m, 8H), 3.50-3.86 (m, 6H), 3.92 (s, 6H), 4.24-4.34 (m, 4H), 6.86 (s, 2H), 7.51 (s, 2H), 7.65 (d, 2H, J=4.4 Hz); FAB MS: m/z 533 (M+H).