Reaction of Dialumane Incorporating Bulky Eind Groups with Pyridines

The reaction of the bulky Eind-based dialumane, (Eind)HAl( μ-H) 2AlH(Eind) ( 1) (Eind = 1,1,3,3,5,5,7,7-octaethyl- s-hydrindacen-4-yl), with pyridines is described. When 1 was treated with pyridine (Py) in toluene, the Py adduct of aryldihydroalumane, Py→AlH 2(Eind) ( 2), was initially formed. Then, the hydroalumination of Py took place to yield the Py-bound aryl(1,4-dihydropyrid-1-yl)hydroalumane, Py→AlH(1,4-dihydropyrid-1-yl)(Eind) ( 3). A similar reaction with a stronger Lewis base, 4-pyrrolidinopyridine (PPy), produced the stable PPy adduct, PPy→AlH 2(Eind) ( 4). The resulting organoaluminum compounds have been fully characterized by NMR spectroscopy as well as X-ray crystallography. The reaction mechanism from 1 to 3 via 2 has been examined by deuterium labeling experiments using (Eind)DAl( μ-D) 2AlD(Eind) ( 1-d4). View Full-Tex