Question

Ullanisms, products J. 6.8 and 6.18 Difficulty Level: Medium 99) If 0.10 mol of HSCH,CH,OH reacts at 25°C, sequentially, with 0.20 of CH3CH2Br followed by the addition of H20, which is the major produc is at 25°C, sequentially, with 0.20 mol of Nah, 0.10 mol A) HSCH CHOCH2CH3 B) CH3CH2SCH CH2OH C) CH3CH SCH2CH2OCH2CH3 D) CH2=CH2 E) CH3CH3 HS CH 2 CH 204 + NaH substrate HSCH2CH2OH + NaH in buona te been los products Ans: B Sonop nogi wollt a bout Topic: Predicting mechanisms, products HTRAS HO Sections: 6.8 and 6.18 Difficulty Level: Hard nombolid 43 laidus
why?

Answer 1

CH3CH2-Br oh Nah m o CH3CH2-Br NaH é SVOH HSVOH option one Option B is correct answer. Oxygen is second most electron withdrawing group. So oxygen redily leaves electron and forms anion in presence of base. Oxygen can stabilize the anion. But sulfur has less electron withdrawing ability. But Sulfur still forms anion in presence of base. But it wil not stablize the charge for long time. When electrophile introduces it immediatley reacts. Generally, Sulfur is more reactive nucleophile and a weaker base than oxygen.