a) Which one of the two compounds, CHBr and CHI, will react faster in an S2 reaction with OH⁻?
b) Write the structures of the major products in the following reactions:
i) CHCH=C(CH) + HBr →
ii) CHONa + CHCl →
b) Write the structures of the major products in the following reactions:
i) CHCH=C(CH) + HBr →
ii) CHONa + CHCl →
Solution
(a) \textbf{CHI} — iodide, being larger and a weaker base, departs more easily than bromide.
(b)(i) Markovnikov addition: H goes to the CH carbon, Br to the carbon bearing the two methyls (via the more stable 3° carbocation):
(2-bromo-2-methylbutane).
(ii) Williamson synthesis:
(ethoxybenzene / phenetole).
(b)(i) Markovnikov addition: H goes to the CH carbon, Br to the carbon bearing the two methyls (via the more stable 3° carbocation):
(2-bromo-2-methylbutane).
(ii) Williamson synthesis:
(ethoxybenzene / phenetole).
CBSE Class 12 Board · 2008 · Foreign · Subjective