I. Organometallic Enantiomeric Scaffolding: Total Synthesis of(-)-Adaline and (-)-Adalinine Using a Key 5-Oxo-PyridinylMolybdenum Scaffold and Featuring a SemipinacolRearrangment/1,5-"Michael-like" Sequence.II. Exchange Reactions of 1-Alkoxy and 1-Sulfonyloxy 3-AllylMolybdenum Complexes