Did you try:
List<myentity> entityList = new List<myentity>(myEntityCollection);
And by the way if you import the System.Linq namespace in order to bring the .ToList() extension method into scope, there's no reason why:
List<myentity> entityList = myEntityCollection.ToList();
wouldn't work as EntityCollection<t> implements IEnumerable<t>.
Refer :
http://stackoverflow.com/questions/7640836/how-to-convert-entitycollectiont-to-listt[
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