There is unoconv for Linux. I am looking something similar for Mac. I think no such a program exists.
On unoconv's gitHub page is stated that:
LibreOffice 220.127.116.11 or later is required to use unoconv under MacOS X. This is the first version distributed with an internal python script that works.
There it's explained too, how to install it.
And being the latest version of LibreOffice v4.0.1, there should be no problem with it.