N-Heterocyclic carbene boranes (NHC-boranes) react with 5-diazo-2,2-dimethyl-1,3-dioxane-4,6-dione at 40 °C in dichloromethane to provide NHC-boryl hydrazone derivatives of 2,2-dimethyl-1,3-dioxane-4,6-dione. These hydrazones disproportionate to bis-hydrazones on treatment with diiodine in dichloromethane at room temperature. The mono- and bis-hydrazones are yellow solids that are stable to chromatography and storage.

中文翻译：

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N-杂环碳硼烷与5-重氮-2,2-二甲基-1,3-二恶烷-4,6-二酮的反应：单-和双-肼基NHC-硼烷的合成

N-杂环卡宾硼烷（NHC-硼烷）与5-重氮-2,2-二甲基-1,3-二恶烷-4,6-二酮在二氯甲烷中在40°C下反应，得到2,2,2的NHC-硼ylzone衍生物-二甲基-1，3-二恶烷-4，6-二酮。在室温下用二碘在二氯甲烷中处理时，这些与双hydr不成比例。一hydr和双hydr为黄色固体，对色谱和储存稳定。