Nitroalkanes, addition Subject

Nitromethane is a detonable explosive, nitroethane can be detonated if both hot and under strong confinement, other nitroalkanes are mild oxidants under ordinary conditions, but precautions should be taken when they are subjected to high temperatures and pressures, since violent reactions may occur [1], Explosives are described consisting of nitromethane stabilised for transport by admixture with nitroethane or nitropropane, then resensitised by addition of an amine [4], The polynitroalkanes, being more in oxygen balance than the mono-derivatives, tend to explode more easily [2], and caution is urged, particularly during distillation [3], See also POLYNITROALKYL COMPOUNDS... 

Among the many topics not dealt with in this chapter are intrinsic barrier asymmetry [57], disparity/tightness and their relation to observed Bronsted coefficients [45a, 58], the nitroalkane anomaly and role of additional VB states dissimilar from reactants and products [59], and several other interesting models for FERs [60, 61]. This reviewer was surprised at the lack, as yet, of applications of hybrid quantum-mechanical/molecular-medianical methodology (other than EVB-based methods) for simulations of FERs for any chemical reactions, let alone PT. However, the subject is alive and well, and it is to be expected that many more theoretical simulations of FERs for PT will be performed in the relatively near future. 

In the presence of piperidine in benzene, benzaldehyde reacts with diethyl (nitromethyl)-phosphonate to afford at 67% yield of diethyl (2-hydroxy-l-nitro-2-phenylethyl)phos-phonate, presumably as a mixture of diastereoisomers. However, a similar reaction with 4-nitrobenzaldehyde leads to phosphorus-carbon bond cleavage and the formation of 1-nitro-2-(4-nitrophenyl)ethane. The converse procedure, i.e. a reaction which involves a nitroalkane and an (oxoalkyl)phosphonic diester, is also subject to certain restrictions. The base-catalysed nucleophilic additions of nitromethane to dialkyl acetylphosphonates (Scheme 7 R = Me) to give dialkyl [(1-hydroxy-l-nitromethyl)alkyl]phosphonates have... 

Kurth and co-workers utihzed two 13DC reactions in the same sequence for the synthesis of bis-isoxazolo substituted piperidinone skeleton 214 (Scheme 51) [ 154]. The reaction sequence involved Michael addition of an unsaturated alkoxide 207 to j6-nitrostyrene 75a followed by INOC or ISOC. The resulting isoxazoline intermediate 209 was subjected to Grignard addition for the generation of the isoxazolidine moiety 211, which upon DCC-mediated coupling with nitroacetic ester 212 furnished the intermediate 213 bearing both nitroalkane and alkene moiety. This intermediate upon INOC reaction led to the bis-isoxazolo piperidinone nucleus 214. 

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