When 2-methylcyclohexanone is converted into an enamine, only one product is formed despite the fact that the

Question:

When 2-methylcyclohexanone is converted into an enamine, only one product is formed despite the fact that the starting ketone is unsymmetrical. Build molecular models of the two possible products, and explain the fact that the sole product is the one with the double bond away from the methyl- substitutedcarbon.