Tertiary nitro compounds denitration

Modified Giese reaction.6 The radical obtained by denitration of tertiary nitro compounds undergoes inter- and intramolecular reaction with activated double bonds. 

Tritio-denitration In the presence of azoisobutyronitrile as radical initiator, tri-n-butyltin tritide can tritio-denitrate secondary and tertiary nitro compounds to give the respective labeled derivatives. Primary nitro groups can only be denitrated if they are located adjacent to keto groups . The carbanion-stabilizing properties of nitro groups facilitate the introduction of electrophiles such as alkyl halides, aldehydes and ketones at the a-position. Furthermore, nitroolefins are excellent Michael acceptors as well as dienophiles, which enables the regioselective and chemoselective synthesis of a broad range of acyclic and... 

Contrasted with electrophilic arcmatic nitration, electrophilic aliphatic nitrations are much affected by protolytic denitrations, which particularly with tertiary and secondary nitro compounds are of major in jortance. The fact that denitration affects electrophilic aliphatic nitration can be best demonstrated in the case of 2-nitro-2-methylpropane which was found to undergo protolytic cleavage in FS03H-SbF5, HF-SbF5, and also in HF-PF solution even at -80°. The protolytic cleavage reaction yields tert-butyl cation and nitrous acid (or subsequently, nitrosonium ion). No nitronium ion is formed, as indicated by absence of any... 

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