Unconventional reaction of diazomethane with 1,3,6-trihydroxy-2-methyl-4-nitrobenzene; X-ray crystal structure of (E)-3,6-dihydroxy-2-methyl-1,4-benzoquinone 4-methoxyimine N-oxide

Treatment of 1,3,6-trihydroxy-2-methyl-4-nitrobenzene (protonated 1) with diazomethane produces not only the expected 1-methoxy derivative but also a substantial amount of an isomer with the novel structure (E)-3,6-dihydroxy-2-methyl-1,4-benzoquinone 4-methoxyimine N-oxide (3); the structure of (3) is confirmed by X-ray analysis.