No, you can't do that, a datarow needs a datatable to live. That's the reason I wrote my own entity classes instead of using a datarow class as base class, because it doesn't have an own constructor, it needs a datatable.
The only thing you could do is adding it to another instance of the typed list (but with no data). The other instance will give you the column definitions, so the row should be addable. (you have to use datatable.ImportRow)