Rapid Synthesis of Benzodiazepines by Ring Expansion of Aziridines with Anthranilic Acids by Using a Grinding Technique
作者:Lal Yadav、Atul Singh
DOI:10.1055/s-0031-1289670
日期:2012.2
A grinding-induced, atom-economic, rapid, efficient, one-pot protocol was developed for the synthesis of pharmaceutically relevant benzo-1,4-diazepin-5-ones in excellent yields (72-91%) and high regioselectivities. The method involves a ring-opening-ring-closure cascade of aziridines with anthranilic acids by grinding the neat reactants at room temperature in the presence of lithium bromide as a mild catalyst. Among the advantages of this protocol are its economic viability, the ability to recycle the catalyst, and the formation of water as the only byproduct.