There is no chapter jump tag. What you want is the NCX, and your HTML source marked up to provide regular links to point the <navPoint>s at.
Instructions for this and also the proper tags and syntax to put in the OPF for making the TOC/Beginning accessible via the menu button and having the cover show up properly can be found in the
Amazon Kindle Publishing Guidelines (PDF) which you can download from their website.
Hope this helps.