C# - Track Changes Of Object Contained In Dictionary And Change TKey Accordingly

I am writing a class library to interact with a domain Active Directory. In my object model, I have the following:
Domain;
Organizational Unit;
Group;
User.

In my Domain object, I have an Entries property and an Add() method.
public class Domain {
// The ReadOnlyDictionary<TKey, TValue> is a custom wrapper over an IDictionary.
public ReadOnlyDictionary<string, IDirectoryEntry> Entries { get; }
public void Add(IDirectoryEntry entry) {
Entries.Add(entry.Name, entry);
[Code] .....

For your information, I implemented the INotifyPropertyChanged interface to ease my life, but I don't seem to find a way to make it work the way I want. Perhaps am I not doing things right somehow, as for the location of different methods, I don't know. How can I make my Domain aware of a change that occured within one of its Entries, so that the TKey value is also changed? That is wanted because one could possibly add an entry, change its name meanwhile adding a new entry with the "old" name of the actual within entry, and cause a conflict, etc. In the end, causing the test to fail. But I'd like to make it pass like it actually is. Is there another better approach or workaround?