This is probably not the answer you want to hear but from my experience, I would say "don't bother". I truly wish this would work well, for my own sake, but it never does.

> Is this possible to play with accordion bass buttons?

Theoretically, yes. Practically, I don't think so. I'm assuming you have the normal Stradella bass system. You could play the A with your index finger, the D with your middle finger and the C with your little finger. However, on my accordeon, I always have at least two octaves in the bass so I think it would sound muddy. I also have small hands and playing with my little finger is iffy anyway.

There are two names for this chord that make sense: Am with an added 4th and no 5th or D with no 3rd and an added 2nd (or 9th, depending on where you put it). You could also call it an F6 without the 1st (prime). You could call it a G11 without the 1st and the 7th but that would be silly, _unless_ it happened to be performing the function of the dominant in the key of C or Cm. This list may not be exhaustive, but we're on pretty thin ice already.

The main problems I find with trying to play piano music on the accordeon is the limited range on both sides of the accordeon and the difficulty of switching registers on the discant side quickly enough. Mostly, it just doesn't work. Sorry to be the bearer of bad news, but I hope this helps anyway.