Isocyanilic acids

Diacetylfuroxan, which is described in the older literature as an unstable oil,172 is considerably more stable when obtained in a reasonably pure state, e.g., prepared as described by Peterson.173 It is nevertheless prone to explode on distillation. Two dioximes of this compound are also known.486 Apart from the diaroyl compounds, few other diacylfuroxans have been reported.183,214,240,368 The dialdehyde is produced by nitrous acid deoxi-mation of a-isocyanilic acid (144).487 Otherwise, aldehydes in the furoxan series are unknown. The 3-aldoxime (127) has been found among the fulmi-nuric acid derivatives.371... 

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