Catalyst-Free Synthesis of 2,3-Benzodiazepines via Tetrahydrodiazirino[3,1-a]isoquinoline Reacts with Sulfonyl Chlorides

摘要

An unexpected process from tetrahydrodiazirino[3,1-a]isoquinolines and diversified sulfonyl chlorides RSO2Cl(R=aryl,alkyl)to deliver highly yields 4,5-dihydro-3H-benzo[d][1,2]diazepine skeleton compounds was disclosed via N-insertion ring-opening reaction.The structural framework of 2,3-benzodiazepines is unambiguously confirmed by single-crystal X-ray crystallographic analysis.The present protocol features mild reaction conditions,high yields and feasibility of large-scale synthesis and catalyst-free access to benzo[2,3]diazepines skeleton.In contrast,azomethine imines were produced by employing tetrahydrodiazirino[3,1-a]isoquinoline reacts with aroyl chlorides under the same conditions.