Improved conditions for converting sterically hindered amides to 1,5-disubstituted tetrazoles

Tetrahedron Letters

Volumn 51, Issue 10, 2010, Pages 1404-1406

  Schroeder, Gretchen M ^a   Marshall, Sydney ^a   Wan, Honghe ^a   Purandare, Ashok V ^a  

^a BRISTOL MYERS SQUIBB   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

AMIDE; DIISOPROPYL AZODICARBOXYLATE; DIPHENYL 2 PYRIDYL PHOSPHINE; DIPHENYLPHOSPHORYL AZIDE; PHOSPHINE DERIVATIVE; TETRAZOLE DERIVATIVE; UNCLASSIFIED DRUG;

ARTICLE; CHEMICAL REACTION; LIQUID CHROMATOGRAPHY; MASS SPECTROMETRY;

EID: 75349109441     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2010.01.024     Document Type: Article

References (13)

1. Recent reviews. Zych A.J., and Herr R.J. PharmaChem 6 (2007) 21-24
2. Myznikov L.V., Hrabalek A., and Koldobskii G.I. Chem. Heterocycl. Compd. 43 (2007) 1-9
3. May B.C.H., and Abell A.D. Tetrahedron Lett. 42 (2001) 5641-5644
4. Duncia J.V., Pierce M.E., and Santella III J.B. J. Org. Chem. 56 (1991) 2395-2400
5. Athanassopoulos C.M., Garnelis T., Vahliotis D., and Papaioannou D. Org. Lett. 7 (2005) 561-564
6. 3 to give bromo substituted tetrazoles. The bromide could then be removed by reduction with tributyltin hydride. See:. Hajra S., Sinha D., and Bhowmick M. J. Org. Chem. 72 (2007) 1852-1855
7. For a summary of recent methods to prepare 1,5-disubstituted tetrazoles, see:. Katritzky A.R., Cai C., and Meher N.K. Synthesis (2007) 1204-1208
8. Afonso C.M., Barros M.T., Godinho L.S., and Maycock C.D. Tetrahedron 50 (1994) 9671-9678
9. Camp D., and Jenkins I.D. Aust. J. Chem. 41 (1988) 1835-1839
10. Dembinski R. Eur. J. Org. Chem. (2004) 2763-2772
11. Hughes A.B., and Sleebs M.M. J. Org. Chem. 70 (2005) 3079-3088
12. Lal B., Pramanik B.N., Manhas M.S., and Bose A.K. Tetrahedron Lett. (1977) 1977-1980
13. Typical reaction procedure: A test tube was charged with the amide (1 equiv) and diphenyl-2-pyridyl phosphine (4 equiv). The tube was flushed with nitrogen, and THF (0.2 M) was added followed by the dropwise addition of diisopropyl azodicarboxylate (4 equiv). Diphenylphosphoryl azide (4 equiv) was then slowly added dropwise to the homogeneous solution. CAUTION: exotherm. The solution was left to stir in a 45 °C oil bath for 24 h. The reaction mixture was diluted with ethyl acetate and washed with saturated aqueous sodium bicarbonate solution. The organic layer was dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified by flash chromatography (Isco column) eluting with diethyl ether/hexane mixtures to give the desired compounds.