Molecular structures of amino and nitro derivatives of 1,3-di(morpholin-4-yl)benzene

The 4,6-diamino-1,3-di(morpholin-4-yl)- and 5-amino-2,4-di(morpholin-4-yl)-1-nitro derivatives of benzene, which serve as model compounds in studies of spatial structures and reactivities of monomer units of many polymers of practical importance, have been studied by X-ray diffraction analysis. The morpholine rings are twisted so that they are virtually perpendicular to the benzene ring. According to the results of AM1 calculations, the hydrogen atoms of the methylene groups of these substituents carry noticeable positive charges. The introduction of different substituents into the benzene ring has no substantial effect on the charge distribution in the morpholine rings due to the absence of conjugation between the lone electron pairs of the nitrogen atoms of the ring and the π-system of the benzene ring.