Hexane-3,4-dione dioxime

The reaction of hexane-2,5-dione- and cyclohexane-l,4-dione dioximes (representatives of open-chained and cyclic compounds of this series) with acetylene has been studied [272],... 

In the case of hexane-2,5-dione dioxime (KOH/DMSO, 100°C, 1 h, initial acetylene pressure 14 atm), three dipyrroles 8-10 were expected to be formed via the rearrangements involving both methylene and methyl groups in the intermediates (Scheme 1.84). 

SCHEME 1.84 Plausible products of the interaction between hexane-2,5-dione dioxime and acetylene. 

Dioximes of hexane-2,5-dione (81) and cyclohexane-1,4-dione (82) reacted with acetylene under pressure to give dipyrrole 83 and 1,5-divinyl-4,8-dihydropyrrolo[2,3-/]indole (84) in 12% and 6% yields, respectively, thus exemplifying a very simple, straightforward route to inaccessible or unknown pyrrolic assemblies (Equation (22)) (04TL3789). 

Hydroxylamine hydrochloride and sodium carbonate in ethanol with pyrroles lead to dioximes of 1,4-dicarbonyl compounds [109], for example, 2,5-dimethyl-N-alkylpyrroles give the dioxime of hexane-2,5-dione (32) and primary amines R-NH2 ... 

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