Hi,
Now, I don't have boys yet! I'm due with my third child which is a boy. BUT I lived next door to a young mom with two boys the same age as my kids. 1 and 3 years old at the time. Destructive like you wouldn't believe. What I noticed about them, they wanted to get their mother's attention. She was always on the phone or always cleaning, and they would break things or throw things to get her attention. They loved to watch her go "fetch" everything all the time, and even if she was yelling at them, at least it was at THEM! At 16 months, they are testing you to see what they can get away with. They need a negative reation at that age to things that are bad. I don't think a slap on the hand and a firm "NO!" is really that big of a deal. There are people who do, of course. But it works. Do this, and this is going to happen. And you won't like it. I only had to do it a couple of times with my girls, and when they acted up, they would get a look from me that stopped them in their tracks. Also, praise. Praise works great when they do things right. Make a REALLY BIG DEAL when he doesn't throw something, or stops when you say to stop/tell him no. Trust me, it will only get worse with age if you don't set a precedence now. By the age of 3, they'll go toe to toe with you if they think they can do what they want without consequences.
Of course, a thousand books will disagree with me, but I'm going by what I've experienced and what works for me.
Good luck!!!
L.