Originally Posted by Moe Zhoost

The easy way out of this is, like others have said, to break the chain and reroute it properly. If you are an inquisitive sort and want to figure out the cause of the situation, think about doing this:
Have you already replaced your bottom bracket and crank? If so, reverse your work until you get to a point where your chain is ok. I'm not sure what you mean by disconnecting the front derailleur, but if this means that you removed it from the frame, it's likely that that had something to do with it. For larger chainrings, you would have to modify the position of the derailleur; however you don't have to remove it from the frame.