The ketone shown is treated with one equivalent of LDA at $-78^{\circ }$C, followed by one equivalent of methyl iodide. Which structure shown is the major product?

The ketone shown is 2,2-dimethylcyclohexanone. One alpha carbon is quaternary and has no hydrogen, so enolisation is possible only at C6, and kinetic and thermodynamic conditions give the same enolate. Reaction with one equivalent of methyl iodide at carbon gives 2,2,6-trimethylcyclohexanone; the tetramethyl compound needs a second equivalent, and the enol ether is not formed with this soft electrophile.