The Metal-Free, One-Pot Synthesis of Homoallylic Amines by Direct Alkylative Reductive Amination Using Allylsilatrane

Homoallylic amines are versatile scaffolds that can give direct access to heterocycles such as azetidines, pyrrolidines, and quinolines. Existing approaches to synthesize homoallylic amines are typically inefficient, multi-step processes. They are commonly prepared through the allylation of pre-formed imines; such methods require inert conditions and use toxic tin reagents or use expensive titanium catalysts. We have developed a new metal-free, one-pot synthesis of homoallylic amines from aldehydes through direct alkylative reductive amination using 1-allylsilatrane, a bench-stable, easy-to-synthesize, hypercoordinate silane alkylating agent. This open-air reaction is completed in two hours at 40°C and gives good to excellent yields using various substituted anilines and aromatic aldehydes. We also demonstrate multiple utility pathways for homoallylic amines to be used as building blocks for biologically active molecules.