Chronological Synopis -- Achronological story

IMO: If your story is done in non-chronological order, you presumably have a reason. Perhaps multiple storylines building towards a denouement. If you have a good dramatic reason for the order, then that should be reflected in the synopsis so that the synopsis reflects the same building of tension and climax.

If you're doing it in non-chronological order just to screw with people: don't do that.

Or you can acknowledge in the synopsis that the story is achronological.

You need the synopsis to reflect the reader's experience.

Try something like the wikipedia summary of Memento, which is the right length.

https://en.wikipedia.org/wiki/Memento_(film)