The current upswing in the interest in organoelement chemistry of Group 13 metals is attributed not least to the establishment of the coordination chemistry of R(a)E fragments (E=Al, Ga, In; a=1, 2) at d-block metals (M). Recently the availability of low-valent organoelement compounds as building blocks for synthesis has substantially enriched the structure chemistry of this class of compounds. The M-E bonding conditions and the question of the significance of M(d(pi))-E(p(pi)) backbonding as well as potential applications in materials science, for example, as single-source precursors for the deposition of thin intermetallic films by chemical vapor deposition, are discussed.

crystal of dimensions 0.37 x 0.37 x 0.27 mm, rhombohedral. R3, a = b = 15.0677(7), c = 48.7214(49) A, 1 = = 1 102 g~m -~, 2 = 6, j~ = 12.22 cm-', 2328 independent reflections, R(Rw) = 0.105(0.103) for 1309 [I > 20(1)] observed reflections. Maximum final difference Fourier peak 0.83 e k ' . Seifert XRD3000-S, four-circle diffractometer, Cu,, radiation, graphite monochromator, 4 2 0 scan, Om,, = 60". Two set of data were collected due to the instability of the crystal, and although the present set was recorded more quickly the decay factor was 7%. Semiempirical Y-scan absorption correction was applied. Refinement on Fo with full matrix. The structure was solved by direct methods [15] and the molecule was located on a threefold crystallographic axis. An anisotropic thermal model was used for the non-hydrogen atoms, while the thermal and positional parameters for H atoms, which were obtained unambiguously from difference Fourier synthesis, were kept fixed during the last cycles of refinement. The water molecules appear to be disordered and the hydrogen atoms of the water molecule situated on the threefold axis could not be located. Moreover, in spite of the high displacement parameters of the C17-C22 atoms no disorder model could be obtained. The weighting scheme was established as to give no trends in

Good quality, highly monodispersed capped copper metal nanoparticles have been synthesised in a non-hydrolytic approach using thermal decomposition of the Cu(II) precursor [Cu(OCH(Me)CH 2 NMe 2 ) 2 ] in a hot coordinating solvent without further reducing agents; the copper nanoparticles have been characterised by optical spectroscopy (UV/VIS), electron microscopy (TEM), electron diffraction (SAED), and dynamic light scattering (DLS).

Carbonylmetalate dianions react in thf with the group 13 chlorides X m ECl3 - m (E = Al, Ga; X = Cl, Me, Et, iBu; m = 0, 1) to yield the monoanionic species [(CO) n M−EX m Cl2 - m ]- (M = Fe, Cr, Mo, W; n = 4, 5) as the primary products which could be isolated as solvent free salts after exchange with a non coordinating cation. After addition of a chelating Lewis base, e.g., tmeda, dme, and solvent exchange with dichloromethane the primary products undergo a second salt elimination reaction, yielding the neutral intermetallic systems (CO) n M−Ga[X(L)2] (M = Cr, Mo, W, Fe; n = 4, 5; X = Cl, Me, Et; L2 = tmeda, dme, bipy, tBu-dab, thf2) (1−14) and (CO)5M-Al[X(L)2] (M = Cr, Mo, W; X = Cl, Et, iBu; L2 = tmeda, tmpda) (15−20, 23, 24). The chloro derivatives can be converted to the corresponding hydrido or tetrahydridoboranato species which is exemplarily shown by compounds 21 and 22. In the case of R2GaCl (R = Me, Et; 2 equiv) as starting compounds a ligand exchange reaction, generating GaR3, occurs, before the second salt elimination takes place. The new intermetallic systems were characterized by means of elemental analysis and IR, Raman, NMR, and mass spectroscopy. The complexes (CO)5Cr−Ga[Cl(tmeda)] (2), (CO)5W−Al[Et(tmeda)] (20), and (CO)5W−Al[Cl(tmpda)] (23) are also characterized by single-crystal X-ray diffraction. Compounds 2 and 20 crystallize in the monoclinic space group P21/n, Z = 4. 2:  a = 9.059(4) Å, b = 16.084(7) Å, c = 11.835(6) Å, β = 80.6(1)°, V = 1701(1) Å3, and R = 0.037 (R w = 0.118). 20:  a = 8.606(2) Å, b = 16.463(6) Å, c = 12.469(4) Å, β = 93.88(2)°, V = 1762(6) Å3, and R = 0.027 (R w = 0.065). Complex 23 crystallizes in the orthorhombic space group Pccn, a = 23.990(6) Å, b = 9.044(3) Å, c = 15.871(4) Å, V = 3445(1) Å3, and R = 0.044 (R w = 0.088). Ab initio quantum chemical calculations at the MP2 level of theory of the model complexes (CO)5W−E[Cl(NH3)2] (E = B, Al, Ga, In, Tl), (CO)5W−Al[H(NH3)2], (CO)5W−AlH, and (CO)5W−AlCl are reported. The group-13 fragments E(R)L2 behave as strong σ-donors with significant acceptor capabilities. The W−E bonds are strong semipolar covalent bonds with large ionic contributions (D e(calc) between 70 and 120 kcal/mol). Only the W−Tl bond is comparatively weak (D e(calc) = 48 kcal/mol).

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