Bonding analysis in ytterbium(II) distannyl and related tetryls.

The syntheses of the ytterbium(II) distannyl [Yb{Sn(SiMe)}·(thf)] (Yb-Sn) and of its digermyl analogue [Yb{Ge(SiMe)}·(thf)] (Yb-Ge) are presented. The compounds were characterised by multinuclear high-resolution solution NMR spectroscopy, including Yb NMR, and by X-ray diffraction crystallography. The bonding and electronic properties of the two complexes, along with those of the known ytterbium(II) disilyl derivative [Yb{Si(SiMe)}·(thf)] (Yb-Si) and those of the congeneric calcium distannyl [Ca{Sn(SiMe)}·(thf)] (Ca-Sn), were investigated in detail by DFT calculations.

Metal-metal bonded alkaline-earth distannyls.

The first families of alkaline-earth stannylides [Ae(SnPh)·(thf) ] (Ae = Ca, = 3, ; Sr, = 3, ; Ba, = 4, ) and [Ae{Sn(SiMe)}·(thf) ] (Ae = Ca, = 4, ; Sr, = 4, ; Ba, = 4, ), where Ae is a large alkaline earth with direct Ae-Sn bonds, are presented. All complexes have been characterised by high-resolution solution NMR spectroscopy, including Sn NMR, and by X-ray diffraction crystallography. The molecular structures of [Ca(SnPh)·(thf)] (), [Sr(SnPh)·(thf)] (), [Ba(SnPh)·(thf)] (), , and [Ba{Sn(SiMe)}·(thf)] (), most of which crystallised as higher thf solvates than their parents , were established by XRD analysis; the experimentally determined Sn-Ae-Sn' angles lie in the range 158.

Bis(imino)carbazolate: A Master Key for Barium Chemistry.

Reported here is a readily available bis(imino)carbazole-based proligand that constitutes a convenient entry point into the challenging synthetic molecular chemistry of barium. It enables the preparation of rare or even, up to now, unknown, solution-stable heteroleptic barium complexes. The syntheses and structural features for the first molecular barium fluoride and the first barium stannylide, with an unsupported Ba-Sn bond, are described, along with other carbazolate barium species: an amide (both a remarkably stable starting material and an excellent hydrophosphination precatalyst), iodide, and silanylide.

Copper Clusters Containing Hydrides in Trigonal Pyramidal Geometry.

Structurally precise copper hydrides [CuH{SP(OPr)}(C≡CR)], R = Ph (), CHF (), and CHOMe (), were first synthesized from the polyhydrido copper cluster [CuH{SP(OPr)}] with nine equivalents of terminal alkynes. Later, their isolated yields were significantly improved by direct synthesis from [Cu(CHCN)](PF), [NH][SP(OPr)], NaBH, and alkynes along with NEt in THF. , , and were fully characterized by single-crystal X-ray diffraction, ESI-MS, and multinuclear NMR spectroscopy.