You need to have a job in your company in USA to apply for extension. If you do not have any open position within your company in USA , there is no point in applying for one. As your company has to provide details as to what position it is and why it is applying for extension, etc. and why you have not traveled so far on the visa already granted etc.
You can ask your company to place you in USA and ask for extension. Without your employer, you can never do a thing on H1 extension.