Primary Teacher who hates homework here. But (annoyingly) it is something that is expected. You'd be surprised how many parents actually come storming in demanding to know what is going on when you don't set homework one night.
Get the teacher on board (this is essential!). Have a meeting and discuss the issues so s/he knows that you are working to address it, and not just choosing to ignore it and come up with a way together to tackle it. She knows your son and what will motivate him.
I'm not a big fan of punishment for not doing homework. Recess is actually necessary for kids to eat, run around, let off some steam and recharge for the afternoon. Kids who don't get to do that aren't as effective learners. Punishment is not going to encourage them to do homework, it will make them resent it more. They'll end up doing it, but they won't actually learn anything from doing it.
If your son is advanced for his level, is the homework actually too boring for him? Photocopied worksheets are not effective homework, so perhaps you could address that as well. Is there other more effective work he could do? You could suggest some alternatives for him. For example, when we do weights and measures, I ask the children to cook a recipe (of their choice) at home, take a picture of the finished product, and write a short piece about cooking the dish. The kids all love it and I've never had any complaints about them doing it. Another task is to go to the supermarket with their parents and do a few activities around weighing items. Applying what they have learnt to real world tasks is far more important than worksheets.
Also, buy him a really cool diary with whatever character/superhero/etc that he likes. Ditto with a funky folder. Let him pick them. Get the teacher to encourage him to write his homework in the homework diary, and to put any papers needed in the folder so it doesn't get lost. Before you leave school in the afternoon, make sure he has everything he needs to complete the tasks, so there is no excuse for not completing it.
At home, pick a time and place that will become homework time. Generally, sending them to their bedroom and expecting them to get on with it when they're already demotivated isn't going to help. My best suggestion is when you're cooking dinner. Have him set up at the bench/table with his books and start talking to him about his day. What did he play at lunchtime, did they go to the library, how was sport lessons? Then ask about what he learnt that day. What did they learn in maths? Did he understand what he learnt? Ask him to explain it to you (pretend you don't understand and need him to teach you). Get him to complete the homework tasks as part of his showing you what he learnt. Kids often love thinking that they can teach their parents something, and the process of teaching it to you can make him think more effectively about it. It's one thing to know something, but it takes deep understanding to be able to teach it.
Discuss interesting extension work around the tasks he is learning (and trying to teach you). If he's learning about dinosaurs, suggest a trip together to the museum on the weekend, or get on the net together and look up something. Rent a DVD which relates to what is currently being studied, make some popcorn and sit down together to discuss it. Make it fun and interesting and encourage him to look deeper in to what he is learning.
Good luck OP.