I can't see the jeans... "site error", but most pairs of jeans would go with that coat, of all fits, altho I personally think a standard fitting jean, or a slimmer fitting jean, especially, would look much better than a loose fitting pair.
Not something I'd wear personally but I think it works just fine. You might consider a darkish blue instead of the grey though. I think the grey jeans with a black coat might come of as sort of drab and neutral. Switching to a blue might add some color and make the outfit a little more eye catching. Just a thought.