Geminally Substituted Nitroalkanes

Radical anions of geminal nitro compounds in DMF cleave rapidly to nitrite and a radical which initiate a free radical chain in which a v/c-dinitro compound is formed [43]. Radical anions of other a-substituted nitroalkanes may cleave either the nitro group or the other substituent 1-cyano-l-nitrocyclohexane thus splits off nitrite whereas 1-nitrocyclo-hexyl p-tolyl sulfone loses p-tolylsulfinate [44]. 

Excellent nucleophiles in palladium(0)-eatalyzed allylic alkylations are soft carbanions, i.e.. metal salts of C — H acids with a pKa in the range of 10-20. These are activated methylene compounds which are substituted with at least two geminal electron-withdrawing groups [CO.R, S02R, — CN, —NC. COR, N02, (C6H5)2C = N]. As an exception, deprotonated simple nitroalkanes are sometimes also effective as nucleophiles. 

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