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Starting from a nucleophilic Michael addition of nitroform to acrylamide, three synthetic strategies towards 1,1,1‐trinitropropyl‐1‐ammonium salts are described. Due to the high oxygen content and density of one periodate salt, its suitability as high‐energy dense oxidizer in energetic formulations was predicted according to its specific impulse and detonation velocity. Furthermore, those properties were compared to the nitrogen‐rich amino‐bis(5‐tetrazolate) salt. The parameters were calculated with the EXPLO5 (V6.03) computer code and compared to the common solid rocket propellant ammonium perchlorate (AP). Calculations towards the energies of formation were performed using Gaussian 09. Characterization including multinuclear NMR spectroscopy, vibrational analysis (IR, Raman) as well as elemental analysis and a single‐crystal X‐ray diffraction study was performed. The thermal stability was studied using differential scanning calorimetry and the sensitivities against impact and friction were determined.

A variety of energetic compounds combining nitro with nitrocarbamate groups were synthesized. The precursors, polynitro alcohols, were obtained by the condensation of the readily available starting material nitromethane with the small aliphatic aldehydes formaldehyde and glyoxal. The conversion into carbamates was achieved with the reactive chlorosulfonyl isocyanate (CSI) and a final nitration yielded the polynitrocarbamates. The new compounds were fully characterized, including multinuclear NMR spectroscopy, vibrational analysis, mass spectrometry, differential scanning calorimetry, and elemental analysis. The energies of formation were calculated with the GAUSSIAN program package and the detonation parameters were predicted using the EXPLO5 computer code. Due to the positive oxygen balance (Omega(CO)) of the presented compounds, their performance data as oxidizers were determined and compared to the common oxidizer ammonium perchlorate.

New oxygen-rich compounds starting from the amino acids beta-alanine and l-aspartic acid were synthesized and comprehensively analyzed including multinuclear NMR spectroscopy and vibrational spectroscopy. Thermal stabilities were measured and the behavior towards external stimuli like friction or impact were determined. Detonation and combustion parameters were predicted by using the EXPLO5 V6.02 code and were compared with common explosives. In addition, crystal structures were obtained for two compounds.

A simple two step synthesis route for the preparation of several energetic multivalent nitrocarbamates of easily available alcohols is presented. The carbamates were obtained by the reaction of the alcohols and the reactive reagent chlorosulfonyl isocyanate (CSI) with subsequent aqueous work-up. The nitration of the carbamates was performed with mixed acid (nitric and sulfuric acid). The thermal stabilities were explored by using differential scanning calorimetry and the energies of formation were calculated on the CBS-4M level of theory, as well as several detonation and propulsion parameters for the application as energetic materials. All compounds were fully characterized and discussed in addition with single X-ray diffraction.

Two highly energetic nitric acid esters were synthesized from the dimer of dihydroxyacetone. 1,3-Dinitratoacetone (1) and its dimer 2,5-bis(nitratomethyl-2,5-nitrato)-1,4-dioxane (2) were characterized by single-crystal X-ray diffraction, vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, and elemental analysis. The thermal behavior was investigated with DTA measurements. Although showing the same atomic stoichiometry, dimer 2 shows significantly higher sensitivities measured by BAM methods (drophammer and friction tester). Due to the high oxygen content of 62.2%, 1 and 2 were evaluated as potential high energy dense oxidizers.

A 1 % w/w alumina-supported gold catalyst is described that is prepared from the impregnation of alumina with a solution of ammonium tetraazidoaurate(III), NH4[Au(N3)4]. Decomposition of the azide precursor leads to a residue-free catalyst comprised of well-dispersed gold particles. This novel material is tested for propyne hydrogenation using pulse-flow techniques and displays 100 % selectivity to the partial hydrogenation product, propene, albeit in the presence of a large retention of hydrocarbon by the catalyst. The latter characteristic is associated with a support-mediated deactivation pathway. Comparing catalytic performance with a 1.45 % w/w Au/TiO2 reference catalyst indicates that chlorine-free precursor compounds are not required to enhance catalytic activity for this particular reaction.

New polynitro compounds containing a carbonyl biscarbamate moiety derived from the precursor carbonyldiisocyanate were synthesized. In addition, 2, 2-dinitropropane-1, 3-diyl bis(2, 2,2-trinitroethylcarbamate) and 2, 2-dinitropropane-1, 3-diyl bis(2, 2,2-trinitroethyl) dicarbonate, were synthesized using 2, 2-dinitropropane-1, 3-diol as starting material. The compounds were characterized by using the analytical methods, single-crystal X-ray diffraction, vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, elemental analysis, and mass spectrometry. The thermal behavior was investigated with DSC measurements. The suitability of the compounds as potential oxidizers in energetic formulations was determined. The heats of formation of the compounds were calculated with GAUSSIAN 09. The detonation parameters such as the detonation pressure, velocity, energy, and temperature were computed using the EXPLO5 code. For a secure handling of the materials, the sensitivity towards impact, friction, and electrical discharge was tested using the BAM drop hammer, BAM friction tester as well as a small-scale electrical discharge device, respectively.

A new simple synthesis route for 2,2,2-trinitroethyl chloroformate (1), from easily available starting materials 2,2,2-trinitroethanol and phosgene is presented. 2,2,2-Trinitroethyl carbamate (2) was obtained by the reaction of 1 with aqueous ammonia. The nitration of 2 with anhydrous nitric acid and sulfuric acid yields 2,2,2-trinitroethyl nitrocarbamate (3), which has potential as a perchlorate free high energetic dense oxidizer with a high oxygen balance of Ω(CO2) = +14.9 %. The thermal stability was studied using differential scanning calorimetry and the energies of formation were calculated on the CBS-4M level of theory, as well as several detonation parameters and propulsion properties were determined. In addition to full spectroscopic characterization, X-ray diffraction studies were performed for 2 and 3.

A series of (azidomethyl)silanes [Me3SiCH2N3 (1b),Me2Si(CH2N3)2 (2b), MeSi(CH2N3)3 (3b), (CH2)4Si(CH2N3)2 (4b), and (CH2)5Si(CH2N3)2 (5b)] was synthesized, starting from the corresponding (chloromethyl)silanes 1a–3a or (iodomethyl)silanes 4a and 5a. Compounds 1b–5b were characterized by NMR, IR, and Raman spectroscopy. The thermal stabilities of the (azidomethyl)silanes 1b–5b were investigated by DSC, and their impact and friction sensitivities were measured with standard BAM methods. According to these studies, the tris(azidomethyl)silane 3b has to be classified as an extremely sensitive compound.

Tetrakis(2,2,2-trinitroethyl) orthocarbonate (1) and 2,2,2-trinitroethyl formate (2) were synthesized by the reaction of carbon tetrachloride, respectively chloroform, with the corresponding equivalents of 2,2,2-trinitroethanol and catalytic amounts of anhydrous iron(III)chloride. 2,2,2-Trinitroethyl formal (3) was prepared by the condensation of paraformaldehyde with 2,2,2-trinitroethanol. The compounds were fully characterized by single-crystal X-ray diffraction, vibrational spectroscopy (IR and Raman), multinuclear NMR spectroscopy, elemental analysis, and multi-temperature DSC measurements. Due to the positive oxygen balance, the suitability of all three compounds mentioned as potential oxidizers in energetic formulations was investigated and discussed. In addition, the heats of formation of the products were determined experimentally using bomb calorimetric methods. With this value and the experimental (X-ray) density, several detonation parameters such as the detonation pressure, velocity, energy, and temperature were computed using the EXPLO5 code. Furthermore, the sensitivity towards impact, friction and electrical discharge was tested using the BAM drop hammer, a friction tester as well as a small-scale electrical discharge device.

The reaction of organomercury(II) halogenides (RHgHal, Hal = Cl, I) with silver azide furnished the corresponding covalent organomercury(II) azides RHgN3 (R = Me (1), tBu (2), Ph (3)). In addition to the characterization by multinuclear NMR spectroscopy, IR and Raman spectroscopy as well as mass spectrometry, the mercury content was determined. A dependance on the solventpolarity for the 14N NMR resonances was observed. Furthermore, X-ray diffraction studies were performed and the crystal structures for mercury(II) azides 1–3 are reported. A comparison of the bond lengths and angles with data from theoretical calculations is given.

The syntheses of the selenium containing heterocycles dibenzoselenophene (1 ≡ biphenSe) and dibenzo[1,2]diselenine (2 ≡ biphenSe2) were optimized. The halogenation reactions of 1 and 2 with XeF2, SO2Cl2, Br2 and I2 were performed and the corresponding products characterized. In the case of 1, the selenium(IV) dihalogenides, biphenSeF2 (3), biphenSeCl2 (4), biphenSeBr2 (5), and the adduct biphenSe·I2 (6), were isolated and identified. The extremely sensitive selenium(IV) difluoride 3 slowly formed significant amounts of an adduct with HF of the corresponding selenium(IV) oxide biphenSeO·HF (3a) upon storage in glass vessels at low temperatures. In the case of 2, the selenium(IV) trihalogenides, biphen(SeHal3)2 (Hal = F, Cl, Br), were found to be extremely labile (Hal = F) or not detectable (Hal = Cl, Br). Instead, as decomposition products, the selenium chloride species Se2Cl2, SeCl4 and 1 were detected. In the case of Hal = I, the stable adduct biphenSe2·I2 (7) was isolated. In addition to characterization by multinuclear NMR spectroscopy, several molecular structures of biphen-selenium substituted halogenides were determined.

Extremely bulky terphenyltriselanes RSeSeSeR with R = 2,6-(2,4,6-Me3C6H2)2C6H3 and 2,6-(2,4,6-iPr3C6H2)2C6H3 were prepared. The chlorination with sulfuryl chloride resulted in the formation of the corresponding selenenyl chlorides RSeCl. In the case of the methyl substituted derivative, also a chlorination of the mesityl groups was observed and the derivative could be isolated. The molecular structure of the isopropyl substituted triselane [2,6-(2,4,6-iPr3C6H2)2C6H3Se]2Se and that of 2,6-(2,4,6-Me3C6Cl2)2C6H3SeCl, have been determined by X-Ray diffraction.

The tellurenyl fluoride, 2-Me2NCH2C6H4TeF, was obtained from reaction of the tellurenyl iodide RTeI with AgF. The compound was unambiguously identified by 19F and 125Te NMR spectroscopy. The decomposition under disproportionation leads to the tellurium(IV) trifluoride, 2-Me2NCH2C6H4TeF3 and the ditelluride RTeTeR. The fluorination of the ditelluride, (2-Me2NCH2C6H4Te)2, with XeF2 results in pure RTeF3. The molecular structure of 2-Me2NCH2C6H4TeF3, the second structural characterized tellurium(IV) trifluoride, has been determined. Furthermore the syntheses of the new tellurium(IV) difluoride, (2-Me2NCH2C6H4)2TeF2, and corresponding tellurium(IV) diazide, (2-Me2NCH2C6H4)2Te(N3)2 as well as the tellurium(IV) triazide, 2-Me2NCH2C6H4Te(N3)3, and their characterization by spectroscopic methods were reported. During these investigations a rather interesting tellurium(VI) species was formed and the molecular structure of a subsequent product, [(2-Me2NHCH2C6H4)2TeF3O]2(SiF6), was elucidated. Theoretical investigations for the compounds containing the stabilizing 2-dimethylaminomethylphenyl substituent are illustrated.

Fluorination of R2Te (R = 2,4,6-Me3C6H2 (= Mes) (1), 2,4,6-iPr3C6H2 (= Trip) (2)) with xenon difluoride afforded the sterically demanding diorganotellurium(IV) difluorides R2TeF2. The reaction of R2TeF2 (R = Me, Ph, Mes (3), Trip (4)) with trimethylsilyl cyanide resulted in the formation of either R2Te(CN)2 (R = Ph (5), Mes (6)) or the monotellanes R2Te (R = Me, Trip). Upon reaction of Mes2TeF2 (3) with trimethylsilyl azide, dimesityltellurium(IV) diazide Mes2Te(N3)2 (8) was prepared. Characterization by standard methods has been carried out, and in addition, the crystal structures of 1, 3, and (Mes2TeCN)2O (7) were determined, the latter being the first organotellurium(IV) cyanide for which structural information is available.

The preparation and thorough characterization of benzeneselenenyl chlorides, bromides and selenocyanates containing various mesityl substituted groups, i.e. 2, 4, 6-(X3)3C6H2 (X = CH3, CF3, and (CH3)3C), was achieved. Detailed multinuclear NMR studies revealed isotope effects at the selenium-halogen bond. X-ray crystallographic studies on a series of selenenyl species enabled comparisons on the influence of the attached substituents. Eine spektroskopische und strukturelle Untersuchung an sterisch anspruchsvollen (Mesityl, Nonafluormesityl und Supermesityl) Benzolselenenyl-chloriden/bromiden und Selenocyanaten Die Darstellung und vollstandige Charakterisierung von Benzolselenenyl-chloriden, -bromiden und Selenocyanaten mit diversen mesityl-substituierten Gruppen, 2, 4, 6-(X3)3C6H2 (X = CH3, CF3, und (CH3)3C), wird beschrieben. Detaillierte multinukleare NMR-Studien zeigen Isotopeneffekte an der Selen-Halogen Bindung. Einkristallographische Untersuchungen an einer Reihe von Selenenyl-Spezies ermoglichen Vergleiche bezuglich des Einflusses der selen-gebundenen Substituenten.

The reactions of dialkyl tellurides R2Te (R = C2H5, n-C3H7, i-C3H7, c-C6H11) with sulfuryl chloride and bromine were examined. The dialkyltellurium(IV) dichlorides (C2H5)2TeCl2 (1), (n-C3H7)2TeCl2 (2), (i-C3H7)2TeCl2 (3) and (c-C6H11)2TeCl2 (4) were obtained upon reaction with stoichiometric amounts of SO2Cl2. Excess of SO2Cl2 resulted in formation of mixtures of R2TeCl2 and RTeCl3. Treatment of (C2H5)2Te and (n-C3H7)2Te with excess bromine gave the dialkyltellurium(IV) dibromides (C2H5)2TeBr2 (5) and (n-C3H7)2TeBr2 (6), whereas (i-C3H7)2Te and (c-C6H11)2Te yielded the alkyltellurium(IV) tribromides i-C3H7TeBr3 (7) and c-C6H11TeBr3 (8). Equimolar amounts of bromine resulted in mixtures of R2Te and RTeBr3. All products were identified and characterized by analytical and spectroscopic methods. n-Propyl tellurium tribromide (9) was detected from a solution of the dibromide 6 after prolonged periods. The crystal structures of 7, 8 and 9 were determined. Chlorierung und Bromierung von Dialkyltelluriden Die Reaktionen von Dialkyltelluriden R2Te (R = C2H5, n-C3H7, i-C3H7, c-C6H11) mit Sulfurylchlorid und Brom wurden untersucht. Die Dialkyltellur(IV)dichloride (C2H5)2TeCl2 (1), (n-C3H7)2TeCl2 (2), (i-C3H7)2TeCl2 (3) und (c-C6H11)2TeCl2 (4) wurden dabei durch Umsetzung mit stochiometrischen Mengen an SO2Cl2 erhalten. Ein Uberschus an SO2Cl2 ergab Mischungen aus R2TeCl2 und RTeCl3. Bei Verwendung eines Uberschusses an Brom erhielt man fur (C2H5)2Te und (n-C3H7)2Te die Dialkyltellur(IV)dibromide (C2H5)2TeBr2 (5), (n-C3H7)2TeBr2 (6), wahrend (i-C3H7)2Te und (c-C6H11)2Te die Alkyltellur(IV)tribromide i-C3H7TeBr3 (7) und c-C6H11TeBr3 (8) ergaben. Mit aquimolaren Mengen an Brom erhielt man Mischungen aus R2Te und RTeBr3. Alle Verbindungen wurden mit Hilfe analytischer und spektroskopischer Methoden identifiziert und charakterisiert. n-Propyltellurtribromid (9) wurde aus einer Losung von dem Dibromid 6 nach langerem Stehenlassen detektiert. Die Rontgenstrukturanalysen von 7, 8 und 9 wurden bestimmt.

The reaction of 4-(4′-trifluoromethyl-tetrafluorophenoxy)-tetrafluorophenyllithium (RFLi, 1) with halogens, dicyanogen, cyanogen halides, and xenon difluoride was examined. The corresponding halogenated aromatics RFCl (2), RFBr (3) and RFI (4) were formed upon reaction with chlorine, bromine, and iodine. Essentially the same products were isolated in the reaction of 1 with cyanogen chloride, bromide, and iodide, respectively. The nitrile RFCN (5) was obtained from the reaction of 1 with dicyanogen only as a minor product. The reaction of 1 with XeF2 resulted in the isolation of RFCH(CH3)CH2CH3 (6). All products were identified and characterized by analytical and spectroscopic methods. In addition the molecular structures of 2, 3, and 4 have been determined by X-ray crystallography. The reaction enthalpies for the gas phase reactions of pentafluorophenyllithium, C6F5Li, as a model for 1, with XCN (X = F, Cl, Br, I) were calculated. Das Chemische Verhalten von CF3C6F4OC6F4Li gegenuber Halogenen und Halogencyanen Die Reaktion von 4-(4′-Trifluormethyl-tetrafluorphenoxy)-tetrafluorphenyllithium (RFLi, 1) mit Halogenen, Halogencyanen, Dicyan und Xenondifluorid wurde untersucht. Die entsprechenden halogenierten Aromaten RFCl (2), RFBr (3) und RFI (4) entstanden bei der Umsetzung mit Chlor, Brom und Iod. Die gleichen Produkte wurden bei der Reaktion von 1 mit Chlorcyan, Bromcyan und Iodcyan gebildet und isoliert. Das Nitril RFCN (5) wurde erhalten bei der Reaktion von 1 mit Dicyan nur als Nebenprodukt. Die Reaktion von 1 mit XeF2 fuhrte zu der Isolierung von RFCH(CH3)CH2CH3 (6). Alle Produkte wurden mittels analytischer und spektroskopischer Methoden identifiziert und charakterisiert. Die Molekulstrukturen von 2, 3 und 4 wurden bestimmt. Die Reaktionsenthalpien fur die Reaktionen in der Gasphase von Pentafluorphenyllithium, C6F5Li als ein Modell fur 1, mit XCN (X = F, Cl, Br, I) wurden berechnet.

The synthesis of 1,1,1,3-tetranitro-3-azabutane is disclosed and compared with the known method. The structure of 1,1,1,3-tetranitro-3-azabutane is identified by multi-nuclear NMR spectroscopy and X-ray single crystal structure determination.

The reaction of Mes2TeF2 (Mes = 2,4,6-trimethylphenyl) with trimethylsilyl cyanide yields the corresponding tellurium(IV) dicyanide Mes2Te(CN)2. Isolation of suitable crystals allows the determination of the first crystal structure of a compound of the type R2Te(CN)2.

The novel mercury-tellurium cluster [Hg8(μ-n-C3H7Te)12(μ2-Br)Br3] is formed during the reaction of HgBr2 and (n-C3H7Te)2Hg in DMSO. Its crystal structure has been elucidated showing [Hg8(μ-n-C3H7Te)12(μ2-Br)]3+ units with a bromine-centered distorted Hg8 cube. The mercury atoms are bridged by n-C3H7Te— ligands and the resulting clusters are linked to a three-dimensional network by bromine atoms. The close packing of the cluster is mainly determined by the flexible n-propyl residues of the telluride building blocks.