Yes, it is correct to say, "Do you have 2 minutes to talk right now?" when you want to call someone and have a brief conversation. This question is polite and straightforward, indicating that you respect the other person's time and are mindful of their availability.
By asking if they have "2 minutes," you are signaling that you are aware of the limited time you're requesting and that you don't intend to have a lengthy conversation. This can make the person more inclined to respond positively, especially if they are busy or preoccupied at the moment.
Keep in mind that the person might still decline the call or request to talk later, depending on their schedule or current circumstances. It's essential to be understanding and flexible if they are unable to chat right away.