Domestic dogs have adapted to their humans' sleep schedule. But bear in mind that dogs have much better night vision than humans, so feral dogs are more likely to be awake and hunting at night, when it's easier to sneak up on prey.
In fact, that night vision was one of several reasons that we welcomed them into our camps. With dogs sitting around the campfire, watching for predators, we could get a full night's sleep. An uninterrupted period of sleep allows our brain to catalog and organize everything we saw, did and learned during the previous day.
Wolves domesticated themselves (they were attracted by all the perfectly good food we left all over the camp, which we call "garbage") at different times in different regions. But it was generally about 15,000 to 20,000 years ago, and examination of human sites from that time shows clear evidence of a quantum improvement in human thought.
Ironically, this partnership did just the opposite for the dogs. They stopped being hunters and eat whatever we give them, which has much less protein content than the raw meat they were used to. Maintenance of a brain requires an enormous amount of protein, so as they got used to a poorer diet, they became measurably less intelligent than wolves.