PRACTICALLY USABLE C3 BUILDING BLOCKS FOR THE SYNTHESES OF NITRO HETEROCYCLES

Nitromalonaldehyde (NMA-H) is one of useful synthons for synthesizing nitro compounds. However, NMA-H itself cannot be practically employed because of its unstable property. Therefore, sodium salt of NMA-H (NMA-Na) has been used as its synthetic equivalent from old time, and NMA-Na is still important even now albeit several restrictions with regard to safety and treatability. On the other hand, dinitropyridone, nitropyrimidinone and dinitropyrazole can be employed in place of NMA-Na for the same purpose, and furthermore azadienamines, formylnitroenamines and dinitropyrazole also serve as the synthetic equivalents of NMA-H, which are usable in common organic solvents with safety. These reagents condense with dinucleophiles to afford various kinds of nitro compounds.