You can definitely use that approach.
From Apple’s Core Data Programming guide:
Entity inheritance works in a similar way to class inheritance; and is useful for the same reasons. If you have a number of entities that are similar, you can factor the common properties into a superentity, also known as a parent entity. Rather than specifying the same properties in several entities, you can define them in one entity, and the subentities inherit them. For example, you might define a Person entity with attributes firstName and lastName, and subentities Employee and Customer, which inherit those attributes.