Hello cecillovell2, There are two ways to copy iPhone voice memo from to your computer for backup.
One way: Free but just copy from one to one.
Make sure the box is checked under 'music'>'include voice memos. When the sync fails do the following:
Unplug iPhone from the computer after the failed sync
In iTunes, select File –> Library –> Organize Library –> Consolidate files
Plug in the iPhone & sync again.When you are tying to locate a voice memo in the list of voice memos in iTunes, which appears alphabetically as the playlist 'voice memos' amongst your playlists on the right hand side in iTunes, you can search by date.
Two way: Paid, but copy in a time.
Use iPhone to Computer Transfer, which allows you to easily and fast transfer voice memos from iPhone to PC for backup. Then you can upload the iPhone voice memos to YouTube, Facebook, etc. to share those audio recording with your friends, copy an audio CD or add them to iPod touch, iPad.
Choose the suitable way you want according to your demands