A Simple Route to Calcium and Strontium Hydride Clusters. Issue 39 (23rd August 2017)

• Record Type: Journal Article
• Authors: Maitland, Brant; Wiesinger, Michael; Langer, Jens; Ballmann, Gerd; Pahl, Jürgen; Elsen, Holger; Färber, Christian; Harder, Sjoerd
• Is Part Of: Angewandte Chemie international edition. Volume 56:Issue 39(2017)
• Page Start: 11880
• Page End: 11884
• Publication Date: 2017-08-23
• Subjects: alkaline-earth metals -- calcium -- hydrides -- self-assembly -- strontium; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201706786
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The first strontium hydride complex has been obtained by simply treating Sr[N(SiMe3 )2 ]2 with PhSiH3 in the presence of PMDTA. The Sr complex Sr6 H9 [N(SiMe3 )2 ]3 ⋅(PMDTA)3 crystallizes as an "inverse cryptand": an interstitial H − is surrounded by a Sr6 H8 4+ cage decorated with amide and PMDTA ligands. The analogous Ca complex could also be obtained and both retain their solid‐state structures in solution: 1 H NMR spectra in C6 D6 show two doublets and one nonet (4:4:1). Up to 90 °C, no coalescence is observed. The Ca cluster was investigated by DFT calculations and shows atypically low charges on Ca (+1.14) and H (−0.59) which signifies an unexpectedly low ionicity. AIM analysis shows hydride⋅⋅⋅hydride bond paths with considerable electron densities in the bond critical point. The clusters thermally decompose into larger, undefined, metal hydride aggregates. Abstract : Hydride Sr . The first strontium hydride complex has been prepared by a surprisingly simple reaction. The cluster consists of an interstitial hydride, surrounded by an Sr6 octahedron that has eight hydrides capping its faces and is decorated with ligands. Together with its calcium analogue these clusters can be seen as "inverse cryptands". 1 H NMR spectroscopy shows hydride⋅⋅⋅hydride magnetic coupling.