A REEVALUATION OF THE HOFMANN REARRANGEMENT IN ELECTRON-DEFICIENT SYSTEMS - PREPARATION OF 2-(N-15)-AMINO-4,6-DINITROTOLUENE AND 4-(N-15)-AMINO-2,6-DINITROTOLUENE

The Hofmann rearrangement is an excellent synthetic method to introduc e amino functions into aromatic molecules; however, it becomes less ef ficient in electron-deficient systems because of competitive hydrolyti c reactions. This report describes the preparation of the aminodinitro toluenes (ADNTs) 2-(N-15)-amino-4,6-dinitrotoluene and 4-(N-15)-amino- 2,6-dinitrotoluene by developing conditions using HPLC as a reaction m onitoring technique. Both ADNTs were prepared in >70% yield and >95% i sotopic purity by using organic solvents and controlling pH during the formation of N-chlorobenzamides and then performing the rearrangement .