One of those lovely aromas that wafts from kitty's litterbox is ammonia. What is the last thing you want to mix with ammonia? That would be bleach. You are probably aware that it is dangerous to mix bleach and vinegar or bleach and ammonia because toxic chlorine and chloramine vapors are produced. You might be tempted to disinfect the cat box with household bleach after emptying it, but don't use bleach in the first rinse. What you want to do is empty the litterbox, rinse it with water, and then disinfect it with bleach.