Abstract
Genistein ( 1 ) undergoes selective chlorination on treatment with thionyl chloride to give first 8-chlorogenistein ( 10 ) and then 6,8-dichlorogenistein ( 8 ). Biochanin A ( 18 ) gives the 6,8-dichloro derivative 19 . A mechanism is suggested for the unexpected aromatic chlorinations.
Otto Soidinsalo wishes to thank Dr. Jorma Matikainen for guidance in HRMS.