Don’t be spooky
The way I see it, if "let's talk when you get a minute" comes across as spooky that means you already have a communication breakdown and mistrust has already blossomed. Here's a slightly different scenario: You have a disagreement with management; there are many subsequent conversations happening behind the scenes; but no one keeps you in the loop or updates you on what is being decided. In that situation, practically any message (apart from "here is exactly what we are thinking..") comes across as spooky, and you will start reading into what _isnt_ said.
In short, if you think someone might want to know something, and they have a reasonable claim on deserving to know, let them know. Keep people informed, and if you do that then "let's talk when you get a minute" won't feel like such a lurking shadow.