Alpha-Azido Alcohols and Other Short Lived Azides

最近，我们首次证明了α-叠氮醇与醛和联苯二酸建立了快速的平衡。这允许特别简单地获得标题化合物，但在有机合成中处理和利用这些化合物时必须考虑到这一点。α-叠氮醇的两个双基官能团提供的各种可能的反应，应该从力学上进行研究，以便为新产品设计出可行的合成方法。因为标题化合物可以在非常温和的反应条件下被氧化成酰基叠氮化合物，所以我们首次能够使用这个氧化还原过程来生成寿命相当短的甲酰叠氮化物。对相应的Curtius重排反应进行了动力学分析，并与高质量量子化学计算结果进行了比较。甲酰叠氮化物是在惰性气体基质中光化学生成甲酰基硝烯的良好前驱体。叠氮乙炔作为第一个1-叠氮基-1-炔和另一个寿命较短的叠氮化物，将被合成，并通过光谱数据和二次反应进行表征，这表明它是一种富电子的炔和氰卡宾的前体。最初的实验已经取得了成功。最后，还将合成1，1，4，4-四叠氮-2，3-二氮-1，3-丁二烯，以研究导致四唑的异常缓慢的环化反应。

Recently, we showed for the first time that alpha-azido alcohols establish a rapid equilibration with aldehydes and hydrazoic acid. This allows a particularly simple access to the title compounds but has to be taken into account when these compounds are handled and utilized in organic synthesis. The variety of possible reactions, which both geminal functional groups of alpha-azido alcohols offer, should be mechanistically investigated in order to work out practicable synthetic methods for new products. Because the title compounds can be oxidized to acyl azides under very mild reaction conditions, we were able to use this redox process to generate the quite short-lived formyl azide for the first time. The corresponding Curtius rearrangement has been kinetically analyzed, and the resulting activation parameters have been compared with the conclusions of high-quality quantum chemical calculations. Formyl azide is an excellent precursor to photochemically generate formylnitrene in noble-gas matrix. Azidoacetylene, as the first 1-azido-1-alkyne and another short-lived azide, will be prepared and characterized by spectroscopic data and by secondary reactions, which present it as an electron-rich alkyne and a precursor of cyanocarbene. First experiments already were successful. Finally 1,1,4,4-tetraazido-2,3-diaza-1,3-butadiene will also be synthesized to investigate the abnormally slow cyclization that lead to a tetrazole.