Question

3. Determine the classification of the electrophilic starting material (1°, 2°, or 3%). Determine the function of the reagent (Strong Base/ Weak Nuc, Strong Base/ Strong Nuc, Weak Base/ Strong Nuc, Weak Base/Weak Nuc). Draw the product(s) of the following reactions considering possible regioselectivity or regiospecificity, and include stereochemical information when appropriate. If no reaction occurs, write NO REACTION. Label the Major and Minor product(s). NaSCH (a). но HO (b). O Heat (c). Ots Nao HBr

Answer 1

NaSCH₃ -S-CH3 major product нс- minor product Mechanism: OS CH3 -S-CH₃ Na ScH₃ major product SN2 reaction # ha SCH - CH₂ NascH₃ minor product E reaction NaScH₃ is a good nucleophile but weak base so SN2 reaction form major product. En reaction form minor product as NascH₃ is weak base.

H₂O -OH heat minor product CH₂ major product Mechanism: major product H, ő minor product At high temparature Elimination reaction form major product. H₂ is act as good base at high temparature so E, reaction form easily.

major pdt Na o minor product Mechanismi Is ten o CH-H Ez reaction major product mino Ts O Nao осHсна CH₂-H SN2 reaction minor product NaO CH₂ CH3 is a strong base and nucleophile. But for sN2 there is steric hindrance for OCH cHz to attack from the opposite side of leaving group- so it form minor product. NAO CH₂ CH3 is strong base but no steric hindrance for E₂ reaction.

OH HBr Mechanism: Hie > H-Br -H₂O HO CH₃ ►H CH3 H20 major product H₂O HO Nucleophilic attack by opposite side of 3-methy group so no steric hindrance minor product Nucleophilic attack in carbocation have sterie hindrance due to same side attack of 3-methy gr side.