2‐Formylazulene derivatives have been obtained in good yields by the reactions of 2‐methylazulenes with N,N‐dimethylformamide dimethyl acetal, followed by oxidative cleavage of the intermediately formed enamines with NaIO₄. The 2‐formylazulenes obtained were transformed into 2‐ethynylazulenes in good yields by a modification of the Seyferth–Gilbert reaction.

中文翻译：

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2-甲基azulenes的分子转化：2-甲酰基和2-乙腈的高效，实用合成

通过使2-甲基azulenes与N，N-二甲基甲酰胺二甲基乙缩醛反应，然后将中间形成的烯胺与NaIO ₄氧化裂解，可以得到高产率的2-Formylazulene衍生物。通过修饰Seyferth-Gilbert反应，将获得的2-甲酰基azulenes转化为2-乙炔基azulenes，收率很高。