2-ethoxybutane can be made by either reacting butan-2-ol with sodium metal and then ethyl iodide, or by reacting butan-2-ol with tosyl chloride and pyridine and then with sodium ethoxide. When pure (S)-butan-2-ol of specific rotation −13.9º is subjected to the first procedure, 2-ethoxybutane with a specific rotation of −14.3º is obtained as the product. Propose a detailed mechanism, and predict the rotation of 2-ethoxybutane obtained using the second procedure.