Common gotcha with cron is not leaving a blank line at the end. I see you don't have one.
Make sure that command is executed manually first before automating it. If your cli version of PHP needs that exact command to run, great, but it might be different mate. which php should tell you the correct path, if it's even installed, a webserver PHP install isn't necessarily a command line PHP.
Another thing you can try is removing the output redirection (>/dev/nul &2>1 etc). That's so your cron can email you any errors, when it's working properly you can put that back in.
