Question

Et Mode Lasso Select = Insert Space (amino acid Threonine) 22. Draw the reaction mechanism for the Bromination of methoxybenzene showing the sigma complex for both a pars and meta-addition of the electrophile. Then explain how the para substitution is the major product for this reaction. Which resonance form in the sigma complex supports your explanation. (15 points) ОСН3 fe Brs OCH3 Step 1 : OCH Step 2: Reor3 + OCH

Answer 1

Bromination of Methoxy Benzene OCH3 o cha Br27 febry By . (Minor) Brimafor) (para product) Ambr3) . ( orthoproduct) Sheph Step-d Br-for Pears, kun olet peong G + febry (one Electrophile. Step 29) when para addition occur. och olms JB H Br H Br h@ och ochz A, B and C are the Resonance Structures of a complex in which B is major contributor because ist is more stable than others due to th effect L of -ochy lone bairs of o ! overlap with empty porbitals of the Co So para product formed as major product Para product (major)

Slep 26 when meta addition occur. och; - IL 'Br Loo -n - CoD and a car the Resonance structures of the o Complex at meta addi Hon. Here No direct stablization by a Br th effect of rock group in meta product (minor) above given reaction at para addition Sigma Complex [B]. So meta product formed as minor product. ca Mechanisms Stept & Step 2 (9) for para product Stept + Step 2(bl for meta product.