There is a space after the IP:port in your ProxyPass which should not be there.
Based on mod_proxy there should be no space. If someone would just copy&past it and change ServerName and SSLCertificateFile it would not work.
SSLProxyEngine On
ProxyPreserveHost On
ProxyPass / http://127.0.0.1:3415/
ProxyPassReverse / http://127.0.0.1:3415/
Use the pre-formatted tag here should solve the problem. 