5-Hydroxypiperidin-2-one is a versatile building block for the preparation of potentially biologically active compounds. We detail an enantioselective biocatalytic approach towards its synthesis using (S)-hydroxynitrile lyase (HNL)-mediated cyanohydrin formation, followed by hydrogenation. By adjusting the conditions of the latter step, we were able to obtain 5-hydroxypiperidinone-derived (bicyclic) N,N-acetals via an unprecedented reductive amination of the nitrile group, as well as form N-alkylated 5-hydroxypiperidinone in a single step from the same cyanohydrin intermediate.

中文翻译：

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新型的腈还原胺化反应：一种由5-羟基哌啶酮衍生的N，N-缩醛的有效途径

5-羟基哌啶-2-酮是用于制备潜在生物活性化合物的通用构件。我们详细介绍了使用（S）-羟基腈裂解酶（HNL）介导的氰醇形成，然后氢化的对映体选择性生物催化方法。通过调整后一步的条件，我们能够通过空前的腈基还原胺化反应，获得5-羟基哌啶酮衍生的（双环）N，N-缩醛，以及一次形成N-烷基化的5-羟基哌啶酮。步骤从相同的氰醇中间体开始。