POCl3/Sulfoxide and AcCl/Sulfoxide Mediated Chlorination of Pyrrolo[2,1-a]isoquinolines

We have developed an efficient chlorination of pyrrolo[2,1-a]isoquinoline derivatives using POCl3 as thechlorine source and tetramethylene sulfoxide as a promoter. A seriesof pyrrolo[2,1-a]isoquinolines, polysubstituted pyrroles,and naphthols have been readily chlorinated under mild reaction conditions(26 examples, up to >99% yield). AcCl can also act as the chlorinesource competently in this chlorination reaction.

Automated summary

We have developed an efficient chlorination method for pyrrolo[2,1-a]isoquinoline derivatives using POCl3 and tetramethylene sulfoxide as a promoter. Under mild reaction conditions, various pyrrolo[2,1-a]isoquinolines, polysubstituted pyrroles, and naphthols can be readily chlorinated with high yields (up to >99%). AcCl can also serve as a competent chlorine source in this chlorination reaction.