Heavier Alkaline Earth Metal Borohydride Complexes Stabilized by β−Diketiminate Ligand

The reaction of KB[<i>sec</i>-Bu]<sub>3</sub>H with calcium iodide [LCa(μ-I)·thf]<sub>2</sub>] (<b>1</b>) and strontium iodide [LSr(μ-I)·thf]<sub>2</sub> (<b>2</b>) yields calcium tri<i>sec</i>-butylborohydride LCaB(<i>sec</i>-Bu)<sub>3</sub>H·thf (<b>3</b>) and strontium tri<i>sec-</i>butylborohydride LSrB(<i>sec</i>-Bu)<sub>3</sub>H·thf (<b>4</b>) (L = CH(CMe2,6-<i>i</i>Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>N)<sub>2</sub>), respectively. Compounds <b>2</b>, <b>3</b>, and <b>4</b> were characterized by multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, and single crystal X-ray analysis, whereas <b>1</b> was characterized without X-ray structural analysis. Compounds <b>3</b> and <b>4</b> are monomeric in the solid state with a hydride ligation between the metal and boron centers.