Acetylenes from 1,2-dihydrazones

Dihydrazones (readily available from 1,2-diketones) yield acetylenes on oxidation with a variety of oxidizing agents (equation 110). The method is applicable to aliphatic, alicyclic and aromatic dihydrazones. Recently it has been successfully applied in the preparation of cycloalkynes. 

Curtius et ah206 showed that acetylenes can also be prepared by oxidizing vicinal dihydrazones with yellow mercuric oxide. Diphenylacetylene, for example, is thus obtained in 75% yield from benzil dihydrazone.207 In a variant of the Curtius procedure diacetylenes can be prepared in 80-85% yield by oxi-... 

Oxidations with argentic oxide Acetylene derivs. from a-dihydrazones... 

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See also in sourсe #XX -- [ ]

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