Jörg Lorberth

Cyclopentadienyls (CH3)2Mσ-C5H5 of indium, antimony and bismuth

The reaction of Me3In with monomeric cyclopentadiene yields the stable Me2InCp (I): the same product may be obtained by the reaction of (Me2InNMe2)2 with C5H6 via a soluble adduct Me2InCp · HNMe2 (II) which is easily converted into Me2InCp, for which a polymeric structure is suggested. Reactions of Me2SbNMe2 and Me2BiN(Me)SiMe3 with C5H6 afford thermally labile cyclopentadienyls Me2SbCp (III) and Me2BiCp (IV). Compounds I–IV have been studied through IR, 1H NMR and mass spectroscopy; the cyclopentadienyl ligand is σ-bonded to the metals in Me2SbCp and Me2BiCp.

New approach to 1-(phenylethynyl)germatranes and 1-(phenylethynyl)-3,7,10-trimethylgermatrane. Reactions of 1-(phenylethynyl)germatrane with N-bromosuccinimide and bromine

Abstract Reaction of N(CH 2 CHRO) 3 GeBr ( 2a, b ) with LiCCPh affords N(CH 2 CHRO) 3 GeCCPh ( 1a , b ) ( a , R=H; b , R=Me). Compound ( 1b ) was also obtained by treatment of Cl 3 GeCCPh ( 3 ) with N(CH 2 CHMeOSnEt 3 ) 3 ( 4 ). ( 1a ) reacts with N -bromosuccinimide to yield N(CH 2 CH 2 O) 3 GeC(Br) 2 C(O)Ph ( 5 ). Cis -N(CH 2 CH 2 O) 3 GeC(Br)C(Br)Ph ( 6 ) is formed by the reaction of 1a with Br 2 in equivalent amounts. All compounds were characterized by 1 H- and 13 C-NMR spectroscopy and mass spectrometry. Single crystal structures of 1a and 6 were determined by X-ray diffraction studies.

Amino-arsine and -phosphine compounds for the MOVPE of III-V semiconductors

Abstract The alternative group V sources trisdimethylamino-arsine (TDMAAs) and trisdimethylamino-phosphine (TDMAP) have been used as substitutes for the highly toxic group V hydrides AsH 3 and PH 3 for the growth of GaAs, (AlGa)As and InP epitaxial layers by low-pressure metalorganic vapour phase epitaxy (MOVPE). The properties of the layers have been investigated by means of structural (X-ray diffraction), electrical (Hall) and optical (luminescence) methods. The epitaxial layer quality as a function of growth parameters is presented and discussed. GaAs and InP epitaxial layers exhibit narrow X-ray diffraction linewidths (10″ FWHM). Residual n-type carrier concentrations down to 3 × 10 15 and5 × 10 15 cm −3 for GaAs and InP, respectively, with mobilities up to 4300 and 18000 cm 2 /V·s at 77 K are observed. The main acceptor impurity in GaAs and InP layers is carbon, as can be concluded from luminescence measurements. For Al-containing layers, a clear deterioration of the layer quality is observed, caused by the incorporation of nitrogen into the layers, as established by SIMS and X-ray diffraction analysis.

Metallorganische diazoalkane : XVI. Synthese von silyldiazoalkanen Me3Si(LnM)CN2☆

Abstract Silyldiazoalkanes Me 3 Si(L n M)CN 2 (L n M = Me 3 Si, Me 3 Ge, Me 3 Sn, Me 3 Pb; Me 3 As, Me 3 Sb, Me 3 Bi) have been synthesized by three different routes: (a) reactions of the Me 3 SiCHN 2 with metal amides L n MNR 1 R 2 of Group IVB and VB elements, using Me 3 SnCl as catalyst; (b) reactions of the in situ prepared organolithium compound Me 3 SiC(Li)N 2 with organometallic chlorides Me 3 MCl (M = Si, Ge); (c) tincarbon bond cleavage reaction of (Me 3 Sn) 2 CN 2 with Me 3 SiN 3 , affording Me 3 SnN 3 , traces of bis(trimethylsilyl)diazomethane (Me 3 Si)CN 2 , trimethylsilyl(trimethylstannyl)diazomethane Me 3 Si(Me 3 Sn)CN 2 and bis(trimethylsilyl)aminoisocyanide (Me 3 Si) 2 NNC as the major reaction products. IR and NMR data ( 1 H, 13 C, 29 Si, 119 Sn, 207 Pb) of the new heterometal-diazoalkanes are reported and discussed in comparison to relevant compounds of the organometallic diazoalkane series.

Die molekül- und kristallstruktur von thallium-tris(bistrimethylsilylamin), Tl[N(SiMe3)2]3

Abstract The molecular and crystal structure of tris(bistrimethylsilylamin)thallium was determined by means of single-crystal X-ray spectroscopy: in the space group P 3 1 c with a = 16.447(7), c = 8.456(7) A; and D c = 1.149 g cm −3 two molecules are located in the unit cell. The compound is isomorphous to the analogues Fe[N(SiMe 3 ) 2 ] 3 or Al[N(SiMe 3 ) 2 ] 3 , respectively, which show a propellar-twist of the Si 2 N-groups versus the plane of the metal atom and the three nitrogen-atoms: Tl(N) 3 /Si 2 N 49.1°; SiNSi 122.6°; NSiC 111.8°; CSiC 107.1°; TlN 2.089 A;; SiN 1.738 A;; SiC 1.889 A;.

Metallorganische diazoverbindungen : VI. Organische bleidiazoalkane (CH3)3PbC(N2)R☆

Abstract By treating silazane derivatives of lead with aliphatic diazoalkanes the preparation of a series of organometallic lead compounds, derivatives of diazomethane, diazoacetic ester, diazoacetone and diazoacetophenone is reported and characterized by their 1 H NMR, mass and IR spectra and elemental analyses; the interpretation of the mass spectrum of (Me 3 Pb) 2 CN 2 is revised.

Metallorganische diazoverbindungen : VIII. Reaktionen von arsen- und antimonamiden mit diazoessigsäureäthylester

The preparation and properties of the organoarsenic diazoalkanes (Me2N)2-AsC(N2)CO2Et (I), MeAs(NMe2)C(N2)CO2Et (II) and MeAs[C(N2)CO2Et]2 (III), synthesized from the reaction of As(NMe2)3 or MeAs(NMe2)2 with HC(N2)-CO2Et are described; IR, 1H NMR and 13C{1H} PFT spectra of compounds I-III are reported and discussed. Control experiments at room temperature of treatment of Sb(NMe2)3 with CH3CO2Et lead in a smooth reaction to antimony alcoholate, Sb(OEt)3, and CH3CONMe2, whereas As(NMe2)3 did not react; from these results a reaction scheme for analogous, but complex experiments of Sb(NMe2)3 and MeSb-(NMe2)2 with HC(N2)CO2Et is derived.

Metallorganische diazoalkane : IV. Organoquecksilber-diazoketone

Abstract The preparations of organomercury diazoketones RHgC(N2)C(O)R′ and of Hg[C(N2C(O)R′]2, with RCH3, C2H5, R′CH3, C6H5, are described and the spectroscopic properties of the derivatives are reported on the basis of their IR/Raman, 1H NMR and mass spectra.

Synthesis and characterization of aryl bismuth compounds using 2,4,6-triphenylphenyl as a bulky ligand

Abstract Reaction of BiCl 3 with 2,4,6-triphenylphenyllithium in THF solution in a 1:3 ratio, or in toluene solution in a 1:2 ratio affords tris(2,4,6-triphenylphenyl)bismuth ( 1 ) and bis-(2,4,6-triphenylphenyl)bismuth chloride ( 2 ) respectively. 1 can be recrystallized from THF; the crystal structure has been determined with a yellow crystal of composition ( 1 ) · 4.8THF ( 3 ). The comproportionation reaction of 1 with BiCl 3 in a 1:2 ratio, or of 2 with BiCl 3 in a 1:1 ratio gives 2,4,6-triphenylphenylbismuth dichloride ( 4 ). Reduction of 2 with sodium in ammonia, with magnesium in THF, or with cobaltocene in toluene leads only to the isolation of 1,3,5-triphenylbenzene. Similarly, the reduction of 4 with sodium in ammonia, or with magnesium in THF leads only to 1,3,5-triphenylbenzene as a decomposition product, however, reducing 4 with cobaltocene in toulene affords 1 , the latter presumably resulting from a disproportionation reaction of a (not isolated) monovalent bismuth compound, e.g. “2,4,6-triphenylphenylbismuth (I)” ( 6 ).

Die molekül- und kristallstruktur von trimethylzinnazid Me3SnN3

Abstract The electrophilic cleavage reaction of (Me3Sn)2CN2 with the Me3SiN3 in diluted ethereal solution affords well-formed crystals of Me3SnN2 in excellent yield; the azide was investigated by single crystal X-ray methods. Me3SnN3 crystallizes in the pseudohexagonal space group P2/b2/n21/n with Z = 4, dc = 1.960 g cm−3; a = 1172.5(6); b = 679.5(4); c = 875.5(5) pm; V = 697.55 A3. A total of 480 unique non-zero reflections was obtained at room temperature; refining the structure with anisotropic temperature factors for all non-hydrogen atoms and with isotropic temperatures factors for the hydrodgen atoms resulted in a conventional R-value of 0.024. Exactly planar Me3Sn-groups are linked in zig-zag-chains by linear N3-groups while the tin atoms adopt almost ideal symmetric trigonal bipyramidal coordination; the methyl groups of the Me3Sn moieties are arranged in a staggered conformation along the c-axes.