Restarting iphone

What you attempted while connected to the laptop would try to put the device into Recovery Mode. I don't think that is what you want to do. Disconnect the device from the laptop and follow the steps for the force restart. If that does not work, try the steps here, If your iPhone, iPad, or iPod touch won't turn on or is frozen - Apple Support and if that does not work, then use the Get Support link at the top of the page and contact Apple Support. This may also help you if the device is not recognized by the computer. If your computer doesn't recognize your iPhone, iPad, or iPod - Apple Support

You don't need iTunes to restart your iPhone. Try a Force Restart, Force restart iPhone - Apple Support

Why do you want to restart your phone through iTunes?