Screencast 24.1
https://www.youtube.com/watch?v=-p2P5NCeFbg
In this screencast, Andrew Parsons discusses the use of anhydrides to protect amine groups in synthesis.

Screencast 24.2
https://www.youtube.com/watch?v=1yR5vWIE-jo
In this screencast, Andrew Parsons walks you through the mechanism for a reaction of an ester with a Grignard reagent.

Screencast 24.3
https://www.youtube.com/watch?v=3UAdNAcWCEY
In this screencast, Andrew Parsons discusses the reaction mechanism of intramolecular Claisen condensation, known as the Dieckmann reaction.