The preparation of specifically deuterated diphenylamines

Procedures have been developed for the preparation, at levels of label which exceed 90%, of ring-deuterated diphenylamines (DPAs) with the label at specific ring positions. The compounds so prepared are DPA-d 10 , DPA-2,4,6,2′,4′,6′-d 6 , DPA-2,6,2′,6′-d 4 , and DPA-4,4′-d 2 .