There's a 4E feat called Opportunity Knocks found in Martial Power 2. It causes an enemy to grant combat advantage until the end of your next turn when they miss you with an opportunity attack.
Is it correct that with this feat I could
- attack an enemy adjacent to my rogue with my crossbow,
- the enemy gets an Attack of Opportunity
- misses because of my really high defenses against AoOs and
- because the AoO is interrupting my attack, I gain Combat Advantage before my attack takes place
so I can deal Sneak Attack Damage to the foe?