Samarium(0) and 1,1'-Dioctyl-4,4'-Bipyridinium Dibromide: A Novel Electron-Transfer System for the Chemoselective Reduction of Aromatic Nitro Groups
Chengzhi Yu, Bin Liu, and Longqin Hu*
*Department of Pharmaceutical Chemistry, College of Pharmacy, Rutgers, The State University of New Jersey, 160 Frelinghuysen Road, Piscataway, New Jersey 08854-8020, Email: LongHurci.rutgers.edu
C. Yu, B. Liu, L. Hu, J. Org. Chem., 2001, 66, 919-924.
A mild and efficient electron-transfer method for the chemoselective reduction of aromatic nitro groups using samarium(0) metal in the presence of a catalytic amount of 1,1'-dioctyl-4,4'-bipyridinium dibromide gives aromatic amines in good yield with selectivity over a number of other functional and protecting groups.
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The major active reducing agent responsible for the reduction is believed to be the radical cation species formed from 1,1'-dioctyl-4,4'-bipyridinium dibromide
low-valent samarium reagents, reduction of nitro compounds