Complex sentence: In between 1925 and 1945 a large portion of the buildings of the palace were destroyed on the orders of Reza Shah who believed that the centuries old Qajar palace should not hinder the growth of a modern city.
Split into simpler sentences: In between 1925 and 1945, a large portion of the buildings of the palace were destroyed on the orders of Reza Shah. He believed that the centuries old Qajar palace should not hinder the growth of a modern city.