PHOTOCHEMICAL-REACTIONS OF TRANSITION-METAL ORGANYL COMPLEXES WITH OLEFINS

Tricarbonyl-eta5-2,4-pentadien-1-yl-manganese (1), tricarbonyl-eta5-2,4-dimethyl-2,4-pentadien-1-yl-manganese (2) and tricarbonyl-eta5-2,6-cyclohexadien-1-yl-manganese (3) react with 6,6-dimethylfulvene (4) upon irradiation with UV light. By loss of CO and CC bond formations between 6-C of the fulvene and a terminal Sp2-C-atom of the eta5-dienyl ligands the dicarbonyl-eta5:2-2-dienyl-2-cyclopentadiendiyl-propane-manganese chelate complexes 5-7 are formed. However, the main product of the reaction between 3 and 4 is tricarbonyl-eta5-isopropylcyclopentadienylmanganese (8), which is formed by hydride transfer from the eta5-cyclohexadienyl ligand to 6-C of the fulvene. The structures of the products were determined by IR and H-1 NMR spectroscopy.