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The reactivity of neodymium diiodide, NdI2 (1), towards organosilicon, -germanium and -tin halides has been investigated. Compound 1 readily reacts with Me3SiCl in DME to give trimethylsilane (6 %), hexamethyldisilane (4 %) and (Mes

The synthesis of benzene- and pyridinediboronic acids via the organotin compounds was discussed. The organotin compound was dissolved in dry tetrahydrofuran (THF) and treated with a solution of borane in the same solvent under dry nitrogen. The physical characteristics of the compounds formed were found to be in agreement with those found in the literature.

Using a laser flash photolysis/laser probe technique, we report the observation of strong absorption signals in the wavelength region 450-520 nm (highest intensity at 514.5 nm) from four potential precursors of dimethylstannylene, SnMe2, subjected to 193 nm UV pulses. From GC analyses of the gaseous products, combined with quantum chemical excited state CIS and TD calculations, we can attribute these absorptions largely to SnMe2, with SnMe4 as the cleanest source of the species. Kinetic studies have been carried out by time-resolved monitoring of SnMe2. Rate constants have been measured for its reactions with 1,3-C4H6, MeC, CMe, MeOH, 1-C4H9Br, HCl, and SO2. No evidence could be found for reaction of SnMe2 with C2H4, C3H8, Me3SiH, GeH4, Me2GeH2, or N2O. Limits of less than 10-13 cm3 molecule-1 s-1 were set for the rate constants for these latter reactions. These measurements showed that SnMe2 does not insert readily into C-H, Si-H, Ge-H, C-C, Si-C, or Ge-C bonds. It is also unreactive with alkenes although not with dienes or alkynes. It is selectively reactive with lone pair donor molecules. The possible mechanisms of these reactions are discussed. These results represent the first visible absorption spectrum and rate constants for any organo-stannylene in the gas phase.

New stannylboranes were prepared from tetramethylpiperidino dichloroborane or B-bromo-pentamethylborazine with lithium triorganylstannides LiSnR3. Only double stannylation was possible with tmpBCl2 and LiSnMe3, while tmpBCl(SnPh3) was obtained by employing LiSnPh3. This chloride reacted with LiGePh3 to the stannyl germyl borane tmpB(GePh3)(SnPh3). On the other hand, PhMeNBCl2 and an excess of LiSnMe3 gave the borate Li[B(NMePh)(SnMe3)3], which was isolated as a solvate with 4 molecules of THF. The compound is present in the solid state as a solvent separated ion pair. The borate Li(H3BSnMe3) · 2 THF is dimeric in the solid state. Dimerization occurs via two single Li-H-B bridges and a Li-H(B)-Li bridge. The B-Sn bonds in the borates are practically of the same lengths as those in the boranes. In solution all BH bonds of this trihydridoborate are equivalent. Wiley-VCH Verlag GmbH, 2001.

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Calcium atoms are thought to be inserted into E-E' bonds of group 4B catenates, Me3E-E'Me2R (E, E'=Si, Ge, Sn; R=Me, Cl) to give the corresponding Me3E-Ca-E'Me2R compounds.

The preparation of some amino(trimethylstannyl)boranes and their chemical properties are described.With Me3SnLi (Me = CH3) as a reagent only the synthesis of Me3SnB(NR2)2 (1a, b), Me3SnBCl(NR2) (2a, b), and (Me3Sn)2BNR2 (3b) was achieved.The stannylboranes Me3SnB(NR2)2 show astonishing thermal stability.Their Sn - B bonds are broken by hydrogen, the halogens, and chalcogens as well as by alcohols.HCl cleaves the B - N bond.