It's not insider trading, since the stock is not traded on a public market : There's no presumption that all the facts are out in the open. As long as there's no misrepresentation, it's all 'just business'.

How about : "Let me invest right now, so that I won't vote against the FB offer you've got on the table".

Or "If you let me invest now, I can make a recommendation to the FB board that they acquire you".