Why does return 301 send me to a 414 Request?

I have a main domain and a subdomain. I want all traffic to redirect to my subdomain. I have been trying to use return 301 and also rewrite in my nginx.conf for my default domain, but every time I do instead of the url being replaced with my subdomain; the subdomain is added on to the end of the url.

For example: rewrite ^/(.*)$ https://domain2.com/$1 permanent; is the rewrite command I am using and when I type in my domain the url becomes https://domain1.com/domain2.com/domain2.com/domain2.com forever and ever until I get the 414 request.

Any idea what is going on?