We ditched anything that kept Zach contained in a small space after about 10 months. His high chair we kept, but it's only used at his set meal times and he's straight out after. Mobile babies need room.
I've struggled a lot with your issue and I found that as soon as he was mobile it got a lot easier. Does your baby crawl or cruise? If so, ensure the room you keep him in while you are busy (a baby safe one, obviously) has plenty of cruise-height toys or surfaces. Our son cruises around the sofa, the coffee table, his toybox and the TV stand and these have purposely been positioned so he can make his way around the room.
Rotate your toys. Don't always make it real toys either, but use household objects, pots and pans, keys, rice in bottles, shredded paper...Anything baby safe and potentially exciting. Mix it up every day.
Depending on what you are doing, another option is to let baby "help" with your chores. Obviously this wont last very long, but it does give me a few extra seconds. Today for example I let him play with the pegs and the peg basket while I folded some laundry. I sometimes let him play with the safe cutlery while I unload the dishwasher, and his favourite is pushing the vacuum on his knees! I humour it, let him do that for a minute, then vacuum for a minute, then let him at it again, and so on. It stretches chores out but it avoids that horrendous baby whining while you're trying to focus situation.
Don't be afraid of leaving baby while you're busy. Install a playpen or baby gates if you have to. Cover corners with foam edging and all that stuff and then just let go...You've done all you can and baby will be safe for 10 minutes while you clean or even grab a coffee!
I personally also use the TV occasionally. People have different opinions on this, but up to half an hour a day gets the OK in this house and saves my sanity.
I also find changing baby's location can help. If he's been in one room for more than an hour, mix it up. Take baby outside or upstairs with you while you do a job there.
Oh, and work chores around baby, not vice versa. Today I watered the garden and put out washing when Zach made it clear he wanted to play outside. I loaded the dishwasher and swept the kitchen floor while he ate lunch in the kitchen. And so on.
It's really, really tough, but I hope there are a few tips here to make it a bit easier.