Try and find out if the CTO is the only problem, ie. he's not conspiring with the other founder. If the CTO is acting alone, get rid of him and continue with t

Try and find out if the CTO is the only problem, ie. he's not conspiring with the other founder. If the CTO is acting alone, get rid of him and continue with the business. If not, ruin their fundraising chances, cut your losses and move on to bootstrap a business on your own. A prolonged fight won't do you any good.