Q: share documents between iMac and iPhone

Good Morning Rawry 54,

If you have iCloud set up on your iPhone, the best way to share documents is to enable iCloud Drive on your Mac and on your iPhone so that you can access the documents from either device.  Another feature that allows you to share information is AirDrop.  Take a look at the information below:

Apple - iCloud - iCloud Drive
https://www.apple.com/icloud/icloud-drive/​

Share content with AirDrop from your iPhone, iPad, or iPod touch - Apple Support
https://support.apple.com/en-us/HT204144​

Apple - OS X Yosemite - Mac + iOS Continuity
https://www.apple.com/osx/continuity/​

Have a great day!