Reactions of aromatic nitro-compounds. LV. Anionic sigma-complexes of sym-trinitrobenzene with the alkoxides of dihydric alcohols

The reactions of alkoxides of dihydric alcohols with 2,4,6-trinitroanisole and picryl chloride have been studied. The reaction between 2,4,6-trinitroanisole and sodium 2-hydroxyethoxide, 3-hydroxypropoxide, 4-hydroxybutoxide, and 2-methoxyethoxide gives the unsymmetrical 1-methoxy-1-hydroxyalkoxy-2,4,6-trinitrocyclohexa-2,5-dienate sigma-complexes, which are converted on heating into the 1,1-dihydroxyalkoxy-2,4-6-trinitrocyclohexa-2,5-dienate sigma-complexes. In the case of sodium 1-methoxy-1-(..beta..-hydroxyethoxy)-2,4,6-trinitrocyclohexa-2,5-dienate, heating results in intramolecular spirocyclization of the ..beta..-hydroxyethoxy grouping to give sodium 6,8,10-trinitro-1,4-dioxaspiro(4,5)deca-6,9-dienate. The reaction of sodium 3-hydroxy-propoxide, 4-hydroxybutoxide, 2-methoxyethoxide, and diethyleneglycolate with picryl chloride gives the symmetrical 1,1-dihyroxyalkoxy sigma-complexes, while sodium 2-hydroxyethoxide forms a sigma-complex with a 1,3-dioxolane spiro-ring. The composition and structures of the sigma-complexes, isolated as their sodium salts, were established by their elemental analyses and PMR and IR spectroscopy.