The difficulty in accessing and safely utilising non-stabilised diazo species has in the past limited the application of this class of compounds. Here we explore further the use of oxadiazolines, non-stabilised diazo precursors which are bench stable, in direct, non-catalytic, aldehyde C–H functionalisation reactions under UV photolysis in flow and free from additives. Commercially available aldehydes are coupled to afford unsymmetrical aryl–alkyl and alkyl–alkyl ketones while mild conditions and lack of transition metal catalysts allow for exceptional functional group tolerance. Examples are given on small scale and in a larger scale continuous production.

中文翻译：

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使用光流动中产生的不稳定的重氮化合物对乙醛进行C–H官能化处理†

过去，难以获得和安全利用不稳定的重氮类物质限制了这类化合物的应用。在这里，我们进一步探索了在不稳定的，直接的，非催化的，在紫外线光催化下，无流动的，无添加剂的情况下，在直接，非催化的醛CHH功能化反应中稳定使用的非稳定重氮恶唑啉的用途。与市售的醛偶联后可得到不对称的芳基烷基和烷基烷基酮，而温和的条件和缺乏过渡金属催化剂则可实现出色的官能团耐受性。给出了小规模和大规模连续生产的实例。