In the following reaction, the major product (H) is
Grignard tips:
Always attacks carbonyl first
Intramolecular cyclization possible
Workup gives alcohol/ether products
\( \text{M} \xrightarrow{\text{CH}_3\text{MgBr}} \text{N} + \text{CH}_4 \uparrow \xrightarrow{\text{H}^+} \text{CH}_3\text{COCH}_2\text{COCH}_3 \)
Identify the ion having 4f\(^6\) electronic configuration.