Final Answer:
a. Route A: Curved arrow notation: ⇌
b. Route B: Curved arrow notation: ⇢
c. The more reasonable route is a. Route A.
Step-by-step explanation:
In organic chemistry, curved arrow notation is used to represent the movement of electron pairs during chemical reactions. For Route A, the bidirectional arrow (⇌) indicates resonance structures or rapid equilibrium between different electronic configurations. This suggests a stabilized intermediate state, making Route A more reasonable.
Conversely, Route B is represented by a unidirectional arrow (⇢), indicating a one-way flow of electrons. This implies a less favorable or less stable reaction mechanism compared to Route A. The bidirectional arrow in Route A suggests electron delocalization and stability, which is often a characteristic of more reasonable reaction pathways.
The choice between routes often depends on factors such as stability of intermediates, resonance, and electronic configuration. In this case, the bidirectional arrow in Route A suggests a more plausible mechanism with the involvement of resonance structures or equilibrium, making it the more reasonable route. Therefore, the correct answer is option c. Route A.