Bis(amido)diazadiarsetidinide and Amido(imino)arsenide Complexes of Divalent Metals

Abstract

AbstractThe Mg and Ca complexes of the tert‐butyl substituted bis(amido)diazadiarsetidinides [{(tBuNAs)2(tBuN)2}M(thf)2] (M=Mg (1), Ca (6)) were prepared by addition of nBu‐secBuMg or [{(p‐tBu)(C6H4)CH2}2Ca] to [(tBuNAs)2(tBuNH)2] (Ia). Upon evaporation of coordinating THF, 1 is selectively converted to the amido(imino)arsenide complex [Mg{As(NtBu)2}2] (2) whereas 6 decomposes to several products under these conditions. Hydrolysis of 2 with H2O yields the hitherto unknown compound As(NHtBu)3 (3) whereas hydrolysis of Ia leads to the formation of the oxygen bridged bis(amidodiazadiarsetidine) [O{(tBuNH)(tBuNAs)2}2] (4). Reaction of 2 with 3 yields the heteroleptic Mg complex with an amido(imino)arsenide and a bis(amido)diazadiarsetidinide ligand [{(tBuNAs)2(NHtBu)(NtBu)}Mg{As(NtBu)2}] (5). The homologous Ca compound (7) was obtained by conversion of Ia with Ca(hmds)2 (hmds=N(SiMe3)2). Finally, the tetrylene complexes [E{(tBuNAs)2(tBuN)2}] (E=Ge (8), Sn (9), Pb (10)) were prepared by either conversion of Ia with E(hmds)2 for E=Sn, Pb or by addition of the dichlorides of Ge and Sn to [(tBuNAs)2(tBuNLi)2] (Ib). All compounds were characterised by NMR and IR spectroscopy, mass spectrometry and single crystal x‐ray diffraction for 1, 2, 4, 5, 6 and 10.