Germyl Bromide Research Articles

Basic Reactivity Pattern of a Cyclic Disilylated Germylene.

In order to estimate the reactivity of disilylated germylene phosphine adducts, a cyclic version of this compound class was reacted with a number of different reagents. Reactions with the chalcogens sulfur, selenium, and tellurium led to dimers of the heavy ketone analogues. Reactions with water and ethyl bromide proceeded to give the respective oxidized germanol and germyl bromide. Two different reactions with alkynes were observed which led either to a germacyclopropene, by addition of tolane to the germylene, or to a silagermacyclobutene, likely formed by addition of the alkyne across a silagermene. Reaction via the silagermene was also observed in the reaction with benzophenone. Reaction of a germylene phosphine adduct with GeCl2·(dioxane) provided insertion of the silylated germylene into a Ge–Cl bond, leading to a germylated chlorogermylene phosphine adduct.

Density functional theory and Hartree–Fock-density functional theory calculations of 17O, 33S, and 73Ge quadrupole coupling constants

The performance of several density functional theory and Hartree–Fock density functional theory methods in conjunction with Pople type bases for the calculation of 17O, 33S, and 73Ge quadrupole coupling constants in gaseous state molecules was investigated. Assessment of the several models was made by linear regression analysis of the calculated gradient of the molecular electric field versus the experimental nuclear quadrupole coupling constant (NQCCs). Calculations for oxygen on six molecules with the B3LYP/6-311++G(3df,3p) model yield a residual standard deviation of 0.057 MHz (1.4%); for sulfur on 12 molecules with the B3LYP/6-311G(3df,3p) model, 0.42 MHz (1.8%); and for germanium on nine molecules with the B3P86/6-311G(2d) model, 0.83 MHz (1.0%). In the case of germyl acetylene, our calculations indicate that the experimental NQCC reported some time ago by Thomas and Laurie [J. Chem. Phys. 44 (1966) 2602] was incorrectly assigned with respect to algebraic sign. Predictions are made of the 17O and 33S NQCCs in furan, 4H-pyran-4-one, 4H-pyran-4-thione, and 4H-thiapyran-4-thione; and of the 73Ge NQCC in germyl bromide.

Microwave spectra, quadrupole coupling constants, and structure of germyl bromide

The microwave spectra from 26.5 to 39.0 GHz of 74GeH2D79Br, 74GeH2D81Br, 74GeHD2 79Br, 74GeHD2 81Br, 74GeD3 79Br, and 74GeD3 81Br have been measured and assigned. From these data, along with the data obtained earlier for the ’’light’’ compound, the rs structural parameters were determined to be r(Ge–H) = 1.527±0.001 Å, r(Ge–Br) = 2.297±0.001 Å, and ∢HGeBr = 106.3±0.1 °. From a diagnostic least-squares adjustment to fit 16 rotational constants, the following r0 structural parameters were obtained: r(Ge–H) = 1.526±0.002 Å, r(Ge–Br) = 2.299±0.001 Å, and ∢HGeBr = 106.2±0.1 °. The centrifugal distortion and quadrupolar coupling constants have been obtained and compared to those previously reported. The results are compared to similar quantities in related molecules.

Transition-metal carbonyl derivatives of the germanes. Part IV. Germylpentacarbonylrhenium

Physical and spectroscopic properties of germylpentacarbonylrhenium, GeH3Re(CO)5, (I) prepared through reaction of germyl bromide with NaRe(CO)5, are reported and compared with those of the manganese analogue and other related complexes. A further product, isolated in very low yield during the formation of (I), is tentatively identified as bis(pentacarbonylrhenium)germane. GeH2[Re(CO)5]2(II). Ions arising from transfer of hydrogen from Ge to Re are of unusually high abundance in the mass spectrum of (I).

Transition-metal carbonyl derivatives of the germanes. Part I. Germyl tetracarbonylcobalt

Germyltetracarbonylcobalt, GeH3Co(CO)4, has been prepared through reaction of germyl bromide with NaCo(CO)4 in ether, and the [2H3]germyl-analogue GeD3Co(CO)4 obtained similarly. Physical properties and the 1H n.m.r. spectrum are reported, and the vibrational and mass spectra are discussed. The Ge–Co bond is cleaved by HgCl2 and by HCl; adducts are formed with NMe3 and related bases.

Germyl and silyl derivatives of phenol and thiophenol

Phenol reacts with disilyl sulphide to give phenyl silyl ether in high yield. Potassium phenoxide reacts with germyl bromide to give phenyl germyl ether; similarly, silyl and germyl bromides yield the corresponding sulphides with potassium benzenethiolate. The i.r. and n.m.r. spectra of these new compounds are reported and discussed. Their reactions with boron trifluoride and boron trichloride are described: these included cleavage, adduct formation, and acid-catalysed disproportionation.

Preparation and properties of trigermyl-arsine and -stibine

Trigermyl-arsine and -stibine have been prepared in high yield by the reactions of germyl bromide with trisilylarsine and -stibine; n.m.r., i.r., and Raman spectra have been recorded and assigned.

Studies in germyl chemistry. Part III. Trigermylphosphine

Trigermylphosphine has been prepared in high yield from trisilylphosphine and germyl bromide, and its mass, vibrational, u.v., and n.m.r. spectra have been determined; the vibrational spectra indicate that the Ge3P skeleton is not planar. Some reactions of the compound are described.

DERIVATIVES OF MONOGERMANE: PART II. PREPARATION AND PROPERTIES OF GERMYL PSEUDOHALIDES AND RELATED COMPOUNDS

Germyl isocyanate, isothiocyanate, and acetate have been prepared in almost quantitative yield by the interaction of germyl bromide with silver cyanate, thiocyanate, and acetate, respectively. Some of the physical properties of these new germyl derivatives are reported, and their thermal decompositions at moderate temperatures are described. The reaction of germyl bromide with silver oxide or carbonate produces germanium (II) hydride and water instead of digermoxane. Germyl bromide reacts with silver nitrite, forming germane, nitrous oxide, and nitric oxide as the only volatile products.