Anthraquinone diimines

Products isolated from the thermal fragmentation of A-arylbenzamide oximes and A-arylbenzamide O-phenylsulfonyl oximes have been accounted for by invoking a free-radical mechanism which is initiated by the preferential homolysis of the N-O bond." Time-resolved IR spectroscopy has revealed that photolysis of A, A -diphenyl-l,5-dihydroxy-9,10-anthraquinone diimine affords acridine-condensed aromatic products via excited-state intramolecular proton transfer." The absolute and relative rates of thermal rearrangements of substituted benzyl isocyanides have been measured,and it has been found that the relative rates are independent of temperature and exhibit excellent Hammett correlations. Thionitrosoarene (25), thought to be generated by desulfurization of the stable A-thiosulfinylaniline (24), has been established" " as an intermediate in the formation of 3,3a-dihydro-2,l-benzisothiazole (26) from o-alkylthionitrosoarene (24). 

For the preparation of poly(cyclodiborazane)s, a condensation method can also be used. For example, lV,JV -bis(trimethyl-silyl)terephthalaldehyde diimine was reacted with monochloro-dihexylborane to produce a boron-containing polymer with boron-nitrogen four-membered rings (31). This polymerization can be applied to various bis(silylimine)s such as N,N -bis(trimethylsilyl)isophthalaldehyde diimine. However, N,N -bis(trimethylsilyl)anthraquinone diimine gave only the monomeric iminoborane species and no polymer. 

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