Excess sodium amide in liquid ammonia converts the vicinal dibromide shown into propyne, which is deprotonated at its terminal carbon by the same base (before any water work-up). How many moles of $NaNH X_{2}$ are consumed per mole of the dibromide? Give the answer as an integer.

Numerical answer type, tolerance 0.5.

Answer: 3

The compound is 1,2-dibromopropane. Two successive dehydrobromination (E2) steps, each using one mole of amide, give propyne. The terminal alkyne hydrogen is acidic enough to be removed by a third mole of amide, giving sodium propynide. The total consumed is 2 + 1 = 3 mol.

Practice Organic Reaction Mechanisms IV: Elimination More on Substitution vs elimination outcome for drawn substrates

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Excess sodium amide in liquid ammonia converts the vicinal dibromide shown into propyne, which is deprotonated at its terminal carbon by the same base (before any water work-up). How many moles of NaNHX2​ are consumed per mole of the dibromide? Give the answer as an integer.

Answer: 3

More questions on Substitution vs elimination outcome for drawn substrates

Excess sodium amide in liquid ammonia converts the vicinal dibromide shown into propyne, which is deprotonated at its terminal carbon by the same base (before any water work-up). How many moles of $NaNH X_{2}$ are consumed per mole of the dibromide? Give the answer as an integer.