Reduction to alcohol then dehydration to alkene

Steps:

• Propanoic acid (CH3CH2COOH) requires reduction to propan-1-ol (CH3CH2CH2OH) in stage 1.
• Propan-1-ol then needs dehydration to propene (CH3CH=CH2) in stage 2.
• LiAlH4 reduces carboxylic acids to primary alcohols via hydride addition and workup.
• Conc. H2SO4 dehydrates primary alcohols to alkenes at high temperature via E1 mechanism.

Why A is correct:

• LiAlH4 fully reduces RCOOH to RCH2OH (unlike milder agents), and conc. H2SO4 catalyzes dehydration per Zaitsev's rule, yielding propene from propan-1-ol.

Why the others are wrong:

• B: NaOH in ethanol neutralizes but does not dehydrate alcohols to alkenes.
• C: NaBH4 reduces aldehydes/ketones but not carboxylic acids, so no alcohol forms.
• D: NaBH4 fails to reduce the acid, and NaOH in ethanol performs no dehydration.

Final answer: A