Ring-fused aminals: catalyst and solvent-free microwave-assisted α-amination of nitrogen heterocycles
摘要:
A high-yield synthesis of ring-fused aminals via microwave (MW)-assisted alpha-amination of nitrogen heterocycles at 130 degrees C under solvent- and catalyst-free conditions is described. (C) 2008 Elsevier Ltd. All rights reserved.
Facile Access to Ring-Fused Aminals via Direct α-Amination of Secondary Amines with o-Aminobenzaldehydes: Synthesis of Vasicine, Deoxyvasicine, Deoxyvasicinone, Mackinazolinone, and Ruteacarpine
Secondary amines undergo redox-neutral reactions with aminobenzaldehydes under conventional and microwave heating to furnish polycyclic aminals via amine alpha-amination/N-alkylation. This unique alpha-functionalization reaction proceeds without the involvement of transition metals or other additives. The resulting aminal products are precursors for various quinazolinone alkaloids and their analogues.