While it is technically possible to force the OneDrive sync client onto Windows Server 2012 R2 using the workaround, it is an unsupported configuration.
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers] "C:\Program Files\Microsoft OneDrive\OneDrive.exe"="WIN10RTM" "C:\Users\%USERNAME%\AppData\Local\Microsoft\OneDrive\OneDrive.exe"="WIN10RTM"