Domain: Organic / heterocyclic chemistry

Predict the IUPAC name of compound \(\text{X}\) formed in the reaction sequence below.
The starting material, \(\text{1,5-dimethyl-1,2,3,5,6,7-hexahydro-4H-indol-4-one}\), is first treated with \(\text{formic acid}\) to give intermediate \(\text{A}\).
The molecular formula of intermediate \(\text{A}\) is \(\mathrm{C_{10}H_{19}N}\).
In the second step, \(\text{A}\) is heated in the presence of \(\text{palladium on carbon}\) to afford the final product \(\text{X}\).
Based on this transformation sequence and the given molecular formula, determine the IUPAC name of compound \(\text{X}\).

Grading rubric:
criterion: Verifies the role of formic acid as the reducing agent.
weight: 10
criterion: Uses the IUPAC name 1,5-dimethyl-2,3,5,6,7,7a-hexahydro-1H-indol-4-ol for the step 1 product.
weight: 20
criterion: Correctly identifies ring opening to form the enone intermediate 6-methyl-2-(2-(methylamino)ethyl)cyclohex-2-en-1-one.
weight: 20
criterion: Correctly identifies intramolecular imine cyclization forming 1,7-dimethyl-3,3a,4,5,6,7-hexahydro-2H-indol-1-ium.
weight: 20
criterion: Correctly identifies palladium-on-carbon–catalyzed dehydrogenative aromatization as the final transformation step.
weight: 10
criterion: Uses the final IUPAC name 1,7-dimethyl-1H-indole for compound X.
weight: 20

Answer:
1,7-dimethyl-1H-indole