Neutral and cationic Fe(II) beta-diketiminate complexes

The three-coordinate, 12-valence electron complexes [((BDK)-B-Me)FeR] ((BDK)-B-Me = [HC(C(Me)NAr)(2)](-), Ar = 2,6-iPr(2)C(6)H(3), R = CH2Ph, CH2SiMe3) are reported as well as their reactivity towards Lewis bases. With perfluoroaryl borane and -borate type activators, the monoalkyls react to give alkyl-free paramagnetic cationic iron species counterbalanced by perfluorinated arylborate anions. The paramagnetic nature of the cations permits the observation of weak and dynamic interactions with these anions via F-19 NMR spectroscopy. (c) 2005 Elsevier B.V. All rights reserved.