Complications from Dual Roles of Sodium Hydride as a Base and as a Reducing Agent

Sodium hydride is a common reagent for substrate activation in nucleophilic substitution reactions. Sodium hydride can behave both as a base and as a source of hydride. This dual ability in the presence of an electrophile such as benzyl bromide results in the formation of byproducts when dimethylformamide or acetonitrile are used as solvents for these reactions. The structural nature of these byproducts is revealed in this report.

氢化钠（Sodium hydride）是亲核取代反应中用于底物活化的常用试剂。氢化钠兼具碱与氢负离子供体的双重活性。当体系中存在溴化苄（benzyl bromide）等亲电试剂（electrophile），且以N,N-二甲基甲酰胺（dimethylformamide）或乙腈（acetonitrile）作为此类反应的溶剂时，其上述双重活性会引发副产物的生成。本报告揭示了这些副产物的结构本质。