Base-promoted tandem synthesis of nitrogen-containing compounds: MN(SiMe3)2 as potential nitrogen sources

Abstract

Metal silylamides [MN(SiMe₃)₂, M = Li, Na, and K] are widely used Brønsted bases and have become among the most prevalent bases in organic research owing to their commercial availability and low cost. MN(SiMe₃)₂ exhibits strong basicity and high stability, making it a common deprotonation reagent for C–H bond activation. Nitrogen-containing compounds are ubiquitous in pharmaceuticals and natural products, rendering the synthesis of bioactive nitrogen-containing compounds a research priority. Traditionally, the synthesis of these compounds has relied on amines, but the importance of sustainable chemistry is increasing, and the development of efficient and atom-economical synthetic methodologies without compromising compound selectivity and environmental safety is a major theme of research today. In this review, we comprehensively summarize recent advances in the tandem synthesis of nitrogen-containing compounds mediated by MN(SiMe₃)₂ under transition-metal-free conditions. Based on distinct reaction mechanisms, the tandem reactions are classified into two categories: those proceeding via imine intermediates and those involving silylamide intermediates. Moreover, the reaction conditions, functional group universality, reaction mechanism, and applications are discussed in detail, and the prospects and limitations of development in this field are also critically analyzed.