7-Alkyl Indole Synthesis via a Convenient Formation/Alkylation of Lithionitrobenzenes and an Improved Bartoli Reaction

Abstract

A more convenient and efficient method for metalation/alkylation of nitrobenzenes to give 2-substituted nitrobenzenes was developed. Their conversion to 7-alkylindoles using the Bartoli reaction with vinyl magnesium bromide was performed with an improved protocol.

Key words

nitroarenes - lithiation - allylations - alkylations

References

• 1a Köbrich G. Buck P. Chem. Ber.  1970,  103:  1412 
• 1b Buck P. Gleiter R. Köbrich G. Chem. Ber.  1970,  103:  1431 
• 2 Parry RJ. Li Y. Gomez EE. J. Am. Chem. Soc.  1992,  114:  5946 
• 3 Berridge MS. Sayre LM. Arora PK. Terris AH. Riachi NJ. Harik SI. J. Med. Chem.  1993,  36:  1284 
• 4 Pirrung MC. Lee YR. Park K. Springer JP. J. Org. Chem.  1999,  64:  5042 
• 5 Wallace DM. Leung SH. Senge MO. Smith KM. J. Org. Chem.  1993,  58:  7245 
• 6a Bartoli G. Palmieri G. Bosco M. Dalpozzo R. Tetrahedron Lett.  1989,  30:  2129 
• 6b Bartoli G. Bosco M. Dalpozzo R. Palmieri G. Marcantoni E. J. Chem. Soc., Perkin Trans. 1  1991,  2757 
• 6c Bosco M. Dalpozzo R. Bartoli G. Palmieri G. Petini M. J. Chem. Soc. Perkin Trans. 2  1991,  657 
• 6d Dobson DR. Gilmore J. Long DA. Synlett  1992,  79 
• 6e Dobbs AP. Jones K. Veal KT. Tetrahedron Lett.  1997,  38:  5379 
• 6f Dobbs AP. Voyle M. Whittall N. Synlett  1999,  1594 
• 6g Dobbs A. J. Org. Chem.  2001,  66:  638