Question

draw the simplest set of curved arrows that shows how the structure on the left could be turned into the structure on the right. show all lone pairs. if you need to expand part of the structure to show some lone pairs, expand it by drawing in all atoms and bond lines.

Explanation:

Step1: Analyze lone - pairs on oxygen

Oxygen has 6 valence electrons. In the given heterocyclic compound, oxygen is double - bonded to a carbon. So, oxygen has 2 bonding pairs and 2 lone pairs.

Step2: Analyze lone - pairs on nitrogen

Nitrogen has 5 valence electrons. In the compound, nitrogen is double - bonded to a carbon and single - bonded to another carbon. So, nitrogen has 2 bonding pairs and 1 lone pair.

Step3: Show resonance with curved arrows

The lone pair on nitrogen can be delocalized into the ring. The curved arrow should start from the lone pair on nitrogen and point towards the adjacent carbon - carbon double bond. Then, the π - bond electrons of the double bond adjacent to oxygen move towards oxygen to form a new lone pair and give oxygen a negative charge and nitrogen a positive charge.

Answer:

1. Lone pairs: Oxygen has 2 lone pairs and nitrogen has 1 lone pair.
2. Curved arrows: Start the first curved arrow from the lone pair on nitrogen and point it towards the adjacent carbon - carbon double bond. Start the second curved arrow from the π - bond of the double bond adjacent to oxygen and point it towards oxygen.