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

The Mg and Ca complexes of the tert ‐butyl substituted bis(amido)diazadiarsetidinides [{( t BuNAs) 2 ( t BuN) 2 }M(thf) 2 ] (M=Mg ( 1 ), Ca ( 6 )) were prepared by addition of n Bu‐ sec BuMg or [{( p ‐ t Bu)(C 6 H 4 )CH 2 } 2 Ca] to [( t BuNAs) 2 ( t BuNH) 2 ] ( Ia ). Upon evaporation of coordinating THF, 1 is selectively converted to the amido(imino)arsenide complex [Mg{As(N t Bu) 2 } 2 ] ( 2 ) whereas 6 decomposes to several products under these conditions. Hydrolysis of 2 with H 2 O yields the hitherto unknown compound As(NH t Bu) 3 ( 3 ) whereas hydrolysis of Ia leads to the formation of the oxygen bridged bis(amidodiazadiarsetidine) [O{( t BuNH)( t BuNAs) 2 } 2 ] ( 4 ). Reaction of 2 with 3 yields the heteroleptic Mg complex with an amido(imino)arsenide and a bis(amido)diazadiarsetidinide ligand [{( t BuNAs) 2 (NH t Bu)(N t Bu)}Mg{As(N t Bu) 2 }] ( 5 ). The homologous Ca compound ( 7 ) was obtained by conversion of Ia with Ca(hmds) 2 (hmds=N(SiMe 3 ) 2 ). Finally, the tetrylene complexes [E{( t BuNAs) 2 ( t BuN) 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 [( t BuNAs) 2 ( t BuNLi) 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 .