Preparation of α-Free Pyrroles with Perfluorinated Groups at β-Positions

Abstract

Ethyl pyrrole-2-carboxylates bearing trifluoromethyl and/or pentafluorophenyl groups at β-positions were converted to the corresponding α-free pyrroles in good yields by reduction with LiAlH₄, oxidation with MnO₂ and decarbonylation with Pd/C.

Key words

trifluoromethyl - pentafluorophenyl - vinylsulfone - Barton-Zard pyrrole synthesis - α-free pyrrole

References

• 1 The Porphyrin Handbook   Kadash MK. Smith KM. Guilard R. Academic Press; San Diego: 1999. 
• 2a Donohoe TJ. Harji RR. Cousins RPC. Chem. Commun.  1999,  141 
• 2b Dikstra HP. ten Have R. van Leusen AN. J. Org. Chem.  1998,  63:  5332 
• 2c ten Have R. Leusink FR. van Leusen AN. Synthesis  1996,  871 
• 2d Magnus P. Gallagher T. Schultz J. Or Y.-S. Ananthanarayan TP. J. Am. Chem. Soc.  1987,  109:  2706 
• 3a Ono N. Muratani E. Ogawa T. J. Heterocycl. Chem.  1991,  28:  2053 
• 3b Also see: van Leusen D. Flentge E. van Leusen AM. Tetrahedron.  1991,  47:  4639 
• 4 van Leusen D. van Echten E. van Leusen AM. J. Org. Chem.  1992,  57:  2245 
• 5 Murashima T. Shiga D. Nishi K. Uno H. Ono N. J. Chem. Soc., Perkin Trans. 1  2000,  2671 
• 6 Barton DHR. Zard SZ. J. Chem. Soc., Chem. Commun.  1985,  1098 
• 7a Merz A. Schropp R. Lex J. Angew. Chem. Int. Ed. Engl.  1993,  32:  291 
• 7b Also see: Merz A. Meyer T. Synthesis  1999,  94 
• 8 Liu J.-H. Chan H.-W. Wong HNC. J. Org. Chem.  2000,  65:  3274 
• 9 Sugiura K. Ushiroda K. Johnson MT. Miller JS. Sakata Y. J. Mater. Chem.  2000,  10:  2507 
• 10 Uno H. Tanaka M. Inoue T. Ono N. Synthesis  1999,  471 
• 11a Arnord DP. Burgess-Dean L. Hubbard J. Rahman MA. Aust. J. Chem.  1994,  47:  969 
• 11b Uno H. Sakamoto K. Tominaga T. Ono N. Bull. Chem. Soc. Jpn.  1994,  67:  1441 
• 12a Anderson HJ. Loader CE. Synthesis  1985,  353 
• 12b Demopoulos BJ. Anderson HJ. Loader CE. Faber K. Can. J. Chem.  1983,  61:  2415 
• 13 Uno H. Inoue T. Fumoto Y. Shiro M. Ono N. J. Am. Chem. Soc.  2000,  122:  6773