Reaction of SrI2, EuI2(THF)2, and YbI2(THF)2 with KN(SiMe3)2 and [{(iPr)2ATI}K] ((iPr)2ATI = N-isopropyl-2-(isopropylamino)troponiminate) led to monoaminotroponiminate complexes of the heavier alkaline earth elements and the related divalent lanthanides of composition [{(iPr)2ATI}M{N(SiMe3)2}(THF)2)] (M = Sr, Eu, Yb). Diaminotroponiminate complexes of composition [{(iPr)2ATI}2M(THF)2)] (M = Sr, Ba) were obtained by the reaction of SrI2 and BaI2 with 2 equiv of [{(iPr)2ATI}K]. All new compounds were characterized by single-crystal X-ray diffraction. Independent of the ionic radius of the center metal all monoaminotroponiminate complexes [{(iPr)2ATI}M{N(SiMe3)2}(THF)2] including the previously reported Ca analogue are isostructural. The same phenomenon is observed for [{(iPr)2ATI}2M(THF)2)]. The heterolepetic compounds [{(iPr)2ATI}M{N(SiMe3)2}(THF)2)] were used as catalysts for the intramolecular hydroamination/cyclization reaction of nonactivated aminoalkenes. A decrease in the rate with increasing ion radius of the center metal is observed for the alkaline earth elements. The ytterbium complex, which is oxidized during the catalytic conversion, is also an efficient precatalyst for the hydroamination/cyclization reaction.

Reaction of [Ca{N(SiMe3)2}(THF)2] with the neutral ligands (iPrAT)H and {(iPr)2ATI}H resulted in the corresponding amido complexes [(iPrAT)Ca{N(SiMe3)2}(THF)]2 (iPrAT = 2-(isopropylamino)troponate) and [{(iPr)2ATI}Ca{N(SiMe3)2}(THF)2] ((iPr)2ATI = N-isopropyl-2-(isopropylamino)troponiminate). The solid-state structures of both compounds were established by single-crystal X-ray diffraction. The latter compound showed a high reactivity as catalyst in the intramolecular hydroamination/cyclization reaction of nonactivated amino alkenes.

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Heteroleptic aminotroponiminate complexes of calcium and strontium have been prepared. The monomeric calcium complex [((iPr)2ATI)CaI(THF)3] 1 ((iPr)2ATI = N-isopropyl-2-(isopropylamino)troponiminate) and the corresponding dimeric strontium compound [( (iPr)2ATI)SrI(THF)2]2 2 were obtained by reaction of [((iPr)2ATI)K] and MI2. Whereas the mixed ligand compound of composition [((iPr)2ATI)Ca(iPrAT)]2 3 (iPrAT = 2-(isopropylamino)troponate) was not obtained via a salt metathesis but by reaction of [Ca(N(SiMe3)2)2(THF)2] with ( (iPr)2ATI)H and (iPrAT)H, the diphosphanylamido complex [( (iPr)2ATI)Ca((Ph2P)2N)(THF)2] was obtained by reaction of CaI2 with the potassium compounds [( (iPr)2ATI)K] and [K(THF)n][N(PPh2)2]. The single crystal X-ray structures of all compounds were established and the latter compound shows a eta2-coordination mode of the ligand via the nitrogen and one phosphorus atom.