-
Please review the updated member agreement. Included is a new statement supporting the scientific method and evidence-based medicine. Claims or statements about disease processes should reference widely accepted scientific resources. Theoretical medical speculation is encouraged as part of the overall scientific process. However, unscientific statements that promote unfounded ideological positions or agendas may be removed.
-
Free admissions webinar for pre-vets! “Apply Smarter” Webinar
To be ortho/para, the side groups always donate electrons, making the benzene more susceptible for electrophilic attack, aka activating groups.
Methyl groups donate their electrons by hyperconjugation (refer to ur ochem txtbook or wiki). Electrons in the C-H can temporarily jump in to the p orbital or benzene.
Look at the relative substituents in a molecule.
Electron donating groups will direct the Br ortho and para.
CH3 is a donating group.
Br will be either ortho or para to the CH3 group.
Electron withdrawing groups will donate the Br to the meta position.
COOH is a withdrawing group.
The Br will be in the meta position compared to the COOH group.
The answer given fits these criterias.