Allylic nitromethylation

Peroxid (l-Nitromethyl-allyl)-nitryl-E13/1, 295 (1,3-Dien + N204/... 

Methyl-4-nitro-2-butinyl)-nitryl-E13/1,295 (1,3-Dien + N204/02) (l-Methyl-l-nitromethyl-allyl)-nitryl-E13/1,295 (1,3-Dien + N204/02) (l-Nitromethyl-2-butenyl)-nitryl-E13/1,295(1,3-Dien + N204/02)... 

Oxazol (5R)-5-Methyl-5-nitromethyl-3-phenyl-4,5-dihydro- E16d, 243 (Allyl-N02 + R-CNO)... 

Appropriate nitro-allyl derivatives for condensation to hexatrienes are usually not easily available, with the exception of nitromethyl-l-cyclohexene and nitro-methyl-l-cycloheptene (34)43. Like nitromethane, 34) does not condense with vinamidinium salts (7) and sodium methoxide, but yields insoluble sodium salts. 

Heterogeneous aquacatalytic palladium-catalyzed allylic substitution with nitromethane as the Cl nucleophile has been developed by Uozumi (Scheme 3.71). By using an amphiphilic PS-PEG polymer-supported chiral palladium complex, the asymmetric allyhc nitromethylation of cycloalkenyl esters proceeded smoothly in water. For example, when polymer-supported palladium complex 214 was employed in the asymmetric nitromethylation of cycloheptenyl carbonate 215... 

Nitromethylation. Allylic derivatives, such as carbonates, undergo chain extension to give f )-l-nitroalk-3-enes. 

Homoallylic nitro compounds 845 are accessible by conversion of allylic alcohols to carbonates followed by their palladium-catalyzed solvolysis in nitromethane [618]. Ethoxycarbonylation of the alcohols 843 with ethyl chloroformate provides the corresponding allylic ethyl carbonates in high yields (99% in the case of 844). Exposure of these substrates to catalytic palladium(O) in nitromethane initiates a reaction sequence of ionization - decarboxylation - nitromethylation, which culminates in the formation of nitroalkenes 845. 

Phenylsulphonyl)nitromethane is C-alkylated preferentially by benzyl halides, primary alkyl iodides, and allylic acetates, the latter in the presence of catalytic tetrakis(triphenylphosphine)palladium, providing secondary a-nitrosul-phones (cf. Vol. 5, p. 197). The synthetic utility of this process, other than for the preparation of a-nitrosulphones themselves, has been enhanced by the development of efficient desulphonation processes, " thus providing an overall synthesis of nitroalkanes. Nitroalkanes are also the products of the replacement of tertiary nitro groups by nitromethyl via sodio nitromethane. ... 

---