InfoPath Dev

I have a form I will call "vehicle checkout" it writes to a library called "Vehicle Request" I also have a list call "reservation Log". When I submit the form it is sent to the Vehicle Request library by a submit button. I would then like to write a SharePoint Workflow that will take a piece of the data submitted to the Vehicle Request library and write it to the Reservation Log. Is this possible? An acceptable workaround is to be able to write a data submit rule and add it to my submit button and let infopath write the data in the reservation log.

Ok so here is a follow up, I found out through trial and error that to write from the form you have to submit the form to a SharePoint library and not to a SharePoint list. But the proble i have now is that its being submitted as a form and not to the columns I've made in the libriary.

 Did you promote the fields you want submitted to the library? Go to the home tab with the form in design, click form options then click property promotion then check each field you want displayed in the sharepoint library.