They're not connected. You're good. XC1 was an amazing experience, so if you're even liking XC2 to any degree, you're really going to enjoy the 1st XC game!
Ive heard theres something in the endings. thats why im not sure haha. My girlfriend owns the 3ds version which I might play after if it doesnt screw stuff up for me.
It's not like the second game spoils the first game at all, but there is a certain portion of the ending that will have less of an impact if you haven't finished the first game.