Reactivity of intramolecularly coordinated aluminum compounds to R 3EOH (E = Sn, Si). Remarkable migration of N,C,N and O,C,O pincer ligands

Abstract

The reaction of organoaluminum compounds containing O,C,O or N,C,N chelating (so called pincer) ligands [2,6-(YCH 2) 2C 6H 3]Al i Bu 2 (Y = MeO 1, t BuO 2, Me 2N 3) with R 3SnOH (R = Ph or Me) gives tetraorganotin complexes [2,6-(YCH 2) 2C 6H 3]SnR 3 (Y = MeO, R = Ph 4, Y = MeO, R = Me 5; Y = t BuO, R = Ph 6, Y = t BuO, R = Me 7; Y = Me 2N, R = Ph 8, Y = Me 2N, R = Me 9) as the result of migration of O,C,O or N,C,N pincer ligands from aluminum to tin atom. Reaction of 1 and 2 with ( n Bu 3Sn) 2O proceeded in similar fashion resulting in 10 and 11 ([2,6-(YCH 2) 2C 6H 3]Sn n Bu 3, Y = MeO 10; Y = t BuO 11) in mixture with n Bu 3Sn i Bu. The reaction 1 and 3 with 2 equiv. of Ph 3SiOH followed another reaction path and ([2,6-(YCH 2) 2C 6H 3]Al(OSiPh 3) 2, Y = MeO 12, Me 2N 13) were observed as the products of alkane elimination. The organotin derivatives 4– 11 were characterized by the help of elemental analysis, ESI-MS technique, 1H, 13C, 119Sn NMR spectroscopy and in the case 6 and 8 by single crystal X-ray diffraction (XRD). Compounds 12 and 13 were identified using elemental analysis, 1H, 13C, 29Si NMR and IR spectroscopy.