There has many method to do that,you can find a third part transfer tool,such as Coolmuster Backup Extractor,iPubsoft and so on.
If you want to Transfer Voice Memos from your iPhone to Mac,here is a method
1.Launch iTunes on your Mac.
2.Connect your iPhone to a USB port on the Mac using the iPhone's included USB cable. The icon of your iPhone will appear in the left pane of the iTunes window.
3.Click the "Music" tab at the top of the iTunes window.
4.Click the "Sync Music" check box to select it.
5.Click the "Include Voice Memos" check box to select it.
6.Click "Apply." The voice memos you recorded on your iPhone will transfer to your Mac. They will appear in the "Voice Memos" playlist in iTunes. The voice memos will remain on your iPhone until you delete them using the iPhone. If you delete a voice memo in the iTunes Voice Memos playlist, it will not be deleted from your iPhone.
Read more: http://www.coolmuster.com/idevices/tran ... o-mac.html