Synthetic organic reactions mediated by sodium hydride

Abstract

In synthetic organic chemistry, sodium hydride (NaH) has been utilized almost exclusively as a routine Brønsted base, while NaH has not been considered to work as a hydride donor. Recently, our group has serendipitously found that NaH can function as a unique hydride donor by its solvothermal treatment with sodium iodide (NaI) or lithium iodide (LiI) in tetrahydrofuran (THF) as a solvent. This discovery led to the development of unprecedented reductive molecular transformations such as hydrodecyanation of α-quaternary benzyl cyanides, controlled reduction of amides into aldehydes, dearylation of arylphopsphine oxides, and hydrodehalogenation of haloarenes. Moreover, this concise protocol allows for the use of NaH as enhanced Lewis acid and Brønsted base, enabling directed aromatic C-H sodiation, nucleophilic amination of methoxy arenes, and C2-amination of pyridines (the Chichibabin amination).