Über Chalkogenolate. 151. Untersuchungen über Derivate der N-Thioformyldithiocarbamidsäure. 1. Darstellung und Eigenschaften von N-Thioformyldithiocarbamaten

On Chalcogenolates. 151. Studies on Derivatives of N-Thioformyl Dithiocarbamic Acid. 1. Synthesis and Properties of N-Thioformyl Dithiocarbamates The N-thioformyl dithiocarbamates M[S₂C? NH? CS? H], where M = K, Rb, Cs, Tl, NH₄, [N(ⁿC₄H₉)₄], Na[S₂C? NH? CS? H] · 0.5 H₂O, and Ba[S₂C? NH? CS? H]₂ · 3 HO? CH₂? CH₂? OCH₃ have been prepared by use of partial different procedures. The compounds were characterized with chemical and thermal methods as well as by means of electron absorption, infrared, nuclear magnetic resonance (¹H and ¹³C), and mass spectra. Attempts to synthesize N-thioformyl dithiocarbamic acid were not successful.     

Über Chalkogenolate. 204. Reaktion von Acetamid mit Kohlenstoffdisulfid. 1. Darstellung und Eigenschaften von N-Acetyldithiocarbamaten

On Chalcogenolates. 204. Reaction of Acetamide with Carbon Disulfide. 1. Synthesis and Properties of N-Acetyl Dithiocarbamates Acetamide reacts with carbon disulfide in the presence of a strong base to form via the tetrabutyl ammonium salt the N-acetyl dithiocarbamates M[S₂C? NH? CO? CH₃] with M = Na, K, Rb, Cs, [N(ⁿC₄H₉)₄]. The new compounds have been characterized by means of electron absorption, infrared, nuclear magnetic resonance (¹H and ¹³C), and mass spectra. Attempts to synthesize N-acetyl dithiocarbamic acid were not successful.     

Über Chalkogenolate. 140. Untersuchungen über Dialkylester von Chalkogenokohlensäuren. 3. S,Se-Dialkyldithiomonoselenocarbonate Existenzbeweis von Alkylselenoxanthaten [S2C?SeR]−

On Chalcogenolates. 140. Studies on Dialkyl Esters of Chalcogenocarbonic Acids. 3. S,Se-Dialkyl Dithiomonoselenocarbonates. Evidence for the Existence of Alkyl Selenoxanthates [S₂C? SeR]^? The esters RSe? CS? SR′ with R = R′ = C₂H₅, ⁿC₃H₇ as well as with R = ⁿC₃H₇ and R′ = C₂H₅ have been produced by three different methods. The compounds have been characterized by means of electron absorption, infrared, nuclear magnetic resonance (¹H, ¹³C, and ⁷⁷Se), and mass spectra. The unstable alkyl selenoxanthates M[S₂C? SeR], where M = Na, K and R = C₂H₅, ⁿC₃H₇, are formed by reaction of carbon disulfide with the corresponding alkane selenolate. Freshly prepared they react with alkyl iodides R′I to yield RSe? CS? SR′.     

A device for uranium series leaching from glass fiber in HEPA filter

For the disposal of a high efficiency particulate air (HEPA) glass filter into the environment, the glass fiber should be leached to lower its radioactive concentration to the clearance level. To derive an optimum method for the removal of uranium series from a HEPA glass fiber, five methods were applied in this study. That is, chemical leaching by a 4.0?M HNO₃?C0.1?M Ce(IV) solution, chemical leaching by a 5 wt% NaOH solution, chemical leaching by a 0.5?M H₂O₂?C1.0?M Na₂CO₃ solution, chemical consecutive chemical leaching by a 4.0?M HNO₃ solution, and repeated chemical leaching by a 4.0?M HNO₃ solution were used to remove the uranium series. The residual radioactivity concentrations of ²³⁸U, ²³⁵U, ²²⁶Ra, and ²³⁴Th in glass after leaching for 5?h by the 4.0?M HNO₃?C0.1?M Ce(IV) solution were 2.1, 0.3, 1.1, and 1.2?Bq/g. The residual radioactivity concentrations of ²³⁸U, ²³⁵U, ²²⁶Ra, and ²³⁴Th in glass after leaching for 36?h by 4.0?M HNO₃?C0.1?M Ce(IV) solution were 76.9, 3.4, 63.7, and 71.9?Bq/g. The residual radioactivity concentrations of ²³⁸U, ²³⁵U, ²²⁶Ra, and ²³⁴Th in glass after leaching for 8?h by a 0.5?M H₂O₂?C1.0?M Na₂CO₃ solution were 8.9, 0.0, 1.91, and 6.4?Bq/g. The residual radioactivity concentrations of ²³⁸U, ²³⁵U, ²²⁶Ra, and ²³⁴Th in glass after consecutive leaching for 8?h by the 4.0?M HNO₃ solution were 2.08, 0.12, 1.55, and 2.0?Bq/g. The residual radioactivity concentrations of ²³⁸U, ²³⁵U, ²²⁶Ra, and ²³⁴Th in glass after three repetitions of leaching for 3?h by the 4.0?M HNO₃ solution were 0.02, 0.02, 0.29, and 0.26?Bq/g. Meanwhile, the removal efficiencies of ²³⁸U, ²³⁵U, ²²⁶Ra, and ²³⁴Th from the waste solution after its precipitation?Cfiltration treatment with NaOH and alum for reuse of the 4.0?M HNO₃ waste solution were 100, 100, 93.3, and 100%.     

Reactivity in the gas phase. Behaviour of isoxazoles under negative ion chemical ionization conditions

[M ? H⁺]^? ions of isoxazole (la), 3-methylisoxazole (1b), 5-methylisoxazole (1c), 5-phenylisoxazole (1d) and benzoylacetonitrile (2a) are generated using NICI/OH^? or NICI/NH₂^? techniques. Their fragmentation pathways are rationalized on the basis of collision-induced dissociation and mass-analysed ion kinetic energy spectra and by deuterium labelling studies. 5-Substituted isoxazoles 1c and 1d, after selective deprotonation at position 3, mainly undergo N ? O bond cleavage to the stable α-cyanoenolate NC ? CH ? CR ? O^? (R = Me, Ph) that fragments by loss of R? CN, or R? H, or H₂O. The same α-cyanoenolate anion (R = Ph) is obtained from 2a with OH^?, or NH₂^?, confirming the structure assigned to the [M ? H⁺]^? ion of 1d, On the contrary, 1b is deprotonated mainly at position 5 leading, via N? O and C(3)? C(4) bond cleavages, to H? C ≡ C? O ^? and CH₃CN. Isoxazole (1a) undergoes deprotonation at either position and subsequent fragmentations. Deuterium labelling revealed an extensive exchange between the hydrogen atoms in the ortho position of the phenyl group and the deuterium atom in the α-cyanenolate NC ? CD = CPh ? O^?.     

Über Chalkogenolate. 119. Untersuchungen über N-Nitrocarbamate,N-Nitrocarbamidsäure-O-ethylester und Salze dieses Esters. Versuche zur Darstellung von N-Nitrodithiocarbamaten

On Chalcogenolates. 119. Studies on N-Nitrocarbamates, O-Ethylester of N-Nitrocarbamic Acid, and Salts of this Ester. Attempts to Prepare N-Nitrodithiocarbamates The title compounds M₂[O₂CNNO₂] with M = Na, K, and O₂N? NH? CO? OC₂H₅ as well as M[O₂NNCO? OC₂H₅] with M = NH₄, K, Rb, Cs, Ag, and Hg[O₂NNCO? OC₂H₅]₂ have been prepared. The properties and the electron absorption, infrared, ¹H and ¹³C NMR, and mass spectra are reported and discussed. Attempts to synthesize N-nitrodithiocarbamates under variable conditions were unsuccessful.     

Unusual Nitrile–Nitrile and Nitrile–Alkyne Coupling of FcCN and FcCCCN

The reactions of the Group 4 metallocene alkyne complexes, [Cp*₂M(η²‐Me₃SiC₂SiMe₃)] ( 1 a : M=Ti, 1 b : M=Zr, Cp*=η⁵‐pentamethylcyclopentadienyl), with the ferrocenyl nitriles, Fc?C?N and Fc?C?C?C?N (Fc=Fe(η⁵‐C₅H₅)(η⁵‐C₅H₄)), is described. In case of Fc?C?N an unusual nitrile–nitrile C?C homocoupling was observed and 1‐metalla‐2,5‐diaza‐cyclopenta‐2,4‐dienes ( 3 a , b ) were obtained. As the first step of the reaction with 1 b , the nitrile was coordinated to give [Cp*₂Zr(η²‐Me₃SiC₂SiMe₃)(N?C‐Fc)] ( 2 b ). The reactions with the 3‐ferrocenyl‐2‐propyne‐nitrile Fc?C?C?C?N lead to an alkyne–nitrile C?C coupling of two substrates and the formation of 1‐metalla‐2‐aza‐cyclopenta‐2,4‐dienes ( 4 a , b ). For M=Zr, the compound is stabilized by dimerization as evidenced by single‐crystal X‐ray structure analysis. The electrochemical behavior of 3 a , b and 4 a , b was investigated, showing decomposition after oxidation, leading to different redox‐active products.     

Über Chalkogenolate. 144. Darstellung und Eigenschaften von Alkalimetall-t-butyl-carbonaten,Neue Untersuchungen über Trimethylsilylcarbonate

On Chalcogenolates. 144. Synthesis and Properties of Alkali Metal t-Butyl Carbonates. Reinvestigations of Trimethylsilyl Carbonates The t-butyl carbonates M[O₂C? OC(CH₃)₃], where M = Li, Na, K, Rb, Cs, have been prepared by reaction of the corresponding t-butoxide with CO₂ and characterized by means of diverse methods. The equivalent conductivities of the [O₂C? OC(CH₃)₃]^? ion in aqueous solution have been determined and the Stokes radius, the radius of the hydrated ion, and the diffusion coefficient were calculated. The dissociation constant of t-butyl carbonic acid in water at 25°C is K_a = (1.63 ± 0.03)· 10^?8. The thermodynamic data of dissociation were calculated. New data of trimethylsilyl carbonates [O₂C? OSi(CH₃)₃]^? are given.     

Über Chalkogenolate. 206 [1]. N-Thioacetyldithiocarbamate und Ester der N-Thioacetyldithiocarbamidsäure

On Chalcogenolates. 206. N-Thioacetyl Dithiocarbamates and Esters of N-Thioacetyl Dithiocarbamic Acid Thioacetamide reacts with carbon disulfide in the presence of KH to form via the tetrabutyl ammonium salt dark yellow N-thioacetyl dithiocarbamates M[S₂C? NH? CS? CH₃], where M = K, Rb, Cs. The salts as well as the methyl and ethyl ester have been characterized by means of electron absorption, infrared, nuclear magnetic resonance (¹H and ¹³C), and mass spectra. Attempts to synthesize N-thioacetyl dithiocarbamic acid were not successful.     

Über Chalkogenolate. 159. Umsetzung von 1,2-Ethandithiolaten mit Kohlenstoffdisulfid 1. Darstellung und Eigenschaften von 1,2-Ethan-bis(trithiocarbonaten)

On Chalcogenolates. 159. Reaction of 1,2-Ethanedithiolates with Carbon Disulfide. 1. Synthesis and Characterization of 1,2-Ethane-bis(trithiocarbonates) The reaction of 1,2-ethanedithiolates with carbon disulfide forms the corresponding 1,2-ethane-bis(trithiocarbonates). The compounds M₂[S₂C? SCH₂CH₂S? CS₂] with M = Li, Na, K, Rb, Cs, NH₄, Tl have been characterized with chemical methods as well as by means of electron absorption, infrared, nuclear magnetic resonance (¹H and ¹³C), and mass spectra.     

Halogenometallate von Übergangselementen mit Kationen stickstoffhaltiger heterocyclischer Basen. I. Die Kristallstrukturen von 1,4-Dimethylpiperazinium-tetrachlorocobaltat(II) und -zinkat(II), (dmpipzH2)[MIICl4] (M = Co,Zn)

Halogenometalates of Transition Elements with N-heterocyclic Base Cations. I. The Crystal Structures of 1,4-Dimethylpiperazinium Tetrachlorocobaltate(II) and -zincate(II), (dmpipzH₂)[M^IICl₄] (M = Co, Zn) The compounds (dmpipzH₂)[M^IICl₄] crystallize in the monoclinic space group P2₁/m with a = 6.133(1), b = 14.306(1), c = 6.902(1) Å, β = 90.54(2)°, Z = 2 for M = Co and with a = 6.141(1), b = 14.282(1), c = 6.907(1) Å, β = 90.60(2)°, Z = 2 for M = Zn. The structures consist of tetrahedra [MCl₄]^2? and centrosymmetric cations (dmpipzH₂)²⁺ in the chair form. Bifurcated hydrogen bridging bonds of the N? H …? Cl type connect the nitrogen atom to two chloride ions. Two short distances C …? Cl are interpreted in terms of C? H …?Cl hydrogen bridges.     

Phosphinsubstituierte Chelatliganden. XVIII. Penta- und Tetracarbonylmetall-Komplexe des Chroms,Molybdäns und Wolframs mit sekundären und tertiären Phosphinothioformamid-Liganden

Phosphine Substituted Chelate Ligands. XVIII. Penta- and Tetracarbonylmetal Complexes of Chromium, Molybdenum, and Tungsten with Secondary and Tertiary Phosphinothioformamide Ligands Mono- and bidentately coordinated phosphinothioformamide complexes are obtained by photochemical substitution of the metal hexacarbonyls M(CO)₆ (M ? Cr ( a ), Mo ( b ), W ( c )). The M(CO)₅ · THF adducts react with secondary thioamides under exclusion of light to give the P-coordinate pentacarbonyl complexes [(CO)₅MPPh₂C(S)NHR¹] (R¹ ? Ph ( 1a – c ), Me ( 2a )). The photoreaction of M(CO)₅ · THF with secondary and tertiary thioamides at low temperatures leads to the formation of the P, S-chelate complexes . The corresponding N-silylated complexes 6a – c (R¹ ? Me₃Si, R² ? Ph) are obtained by direct photosubstitution of M(CO)₆ in cyclohexane solution. The labile bis(thioformamide) complexes [(CO)₄M(PPh₂C(S)NHMe)₂] ( 7a – c , cis-trans isomers) are synthesized in low yields according to the same procedure. The attempted alkylation of the chelate complexes 3a – c remains unsuccessful, whereas the secondary thioformamides react with n-BuLi/CH₂Br₂ to give the methylene bis(thioformirnidoesters) [Ph₂PC(NR¹)S]₂CH₂ (R¹ ? Ph (8), Me ( 9 )) in quantitative yields.     

Theoretical Study of the Reactions M++CH3F (M=Ge,As, Se,Sb)

CASSCF–MRMP2 calculations have been carried out to analyze the reactions of the methyl fluoride molecule with the atomic ions Ge⁺, As⁺, Se⁺ and Sb⁺. For these interactions, potential energy curves for the low‐lying electronic states were calculated for different approaching modes of the fragments. Particularly, those channels leading to C? H and C? F oxidative addition products, H₂FC? M? H⁺ and H₃C? M? F⁺, respectively were explored, as well as the paths which evolve to the abstraction (M? F⁺+CH₃) and the elimination (CH₂M⁺+HF) asymptotes. For the reaction Ge⁺+CH₃F the only favorable channel leads to fluorine abstraction by the ion. As⁺ and Sb⁺ can react with CH₃F along pathways yielding stable addition products. However, a viable path joining the oxidative addition product H₃C? M? F⁺ with the elimination asymptote CH₂M⁺+HF was found for the reaction of the fluorocarbon compound with As⁺. No favorable channels were detected for the interaction of fluoromethane with Se⁺. The results discussed herein allow rationalizing some of the experimental data found for these interactions through gas‐phase mass spectrometry.     

Zum Aufbau schlecht geordneter Calciumhydrogensilicate. VII. 29Si-NMR-Untersuchungen an C?S?H(Di,Poly)

On the Structure of Ill-crystallized Calcium Hydrogen Silicates. VII. Solid State ²⁹Si N.M.R. Studies on C? S? H(Di, Poly) High-resolution solid-state MAS ²⁹Si n.m.r. studies prove that C? S? H(Di, Poly) contains end and middle group SiO₄ tetrahedra (di- and polysilicate) only. Further on it is shown that the ratio of OH groups linked to polysilicate to such linked to disilicate anions is constant in the region 1–1.5 CaO/SiO₂ but decreases with increasing temperature of formation of C? S? H(Di, Poly).     

Organometallic polymers. XIV. Copolymerization of vinylcyclopentadienyl manganese tricarbonyl and vinylferrocene with N-vinyl-2-pyrrolidone

N-Vinyl-2-pyrrolidone(I) has been copolymerized with vinylferrocene(II) and vinylcyclopentadienyl manganese tricarbonyl(III) in degassed benzene solutions with the use of azobisisobutyronitrile (AIBN) as the initiator. The polymerizations proceed smoothly, and the relative reactivity ratios were determined as r₁ = 0.66, r₂ = 0.40 (for copolymerization of I with II, M₁ defined as II) and r₁ = 0.14 and r₂ = 0.09 (for copolymerization of I with III, M₁ defined as III). These copolymers were soluble in benzene, THF, chloroform, CCl₄, and DMF. Molecular weights were determined by viscosity and gel-permeation chromatography studies (universal calibration technique.) The copolymers exhibited values of M?_n between 5 × 10³ and 10 × 10³ and M?_w between 7 × 10³ and 17 × 10³ with M?_w/M?_n < 2. Upon heating to 260°C under N₂, copolymers of III underwent gas evolution and weight loss. The weight loss was enhanced at 300°C, and the polymers became in creasingly insoluble. Copolymers of vinylferrocene were oxidized to polyferricinium salts upon treatment with dichlorodicyanoquinone (DDQ) or o-chloranil (o-CA) in benzene. Each unit of quinone incorporated into the polysalts had been reduced to its radical anion. The ratio of ferrocene to ferricinium units in the polysalts was determined. The polysalts did not melt at 360°C and were readily soluble only in DMF.     

Fourier transform NMR studies of organometallic compounds. II—synthesis and NMR spectroscopy of propenyl and isopropenyl derivatives of silicon and lead

Isomeric mixtures of compounds Me_nM(CH?CHMe)_4?n (M=Si, Pb; n=0?3) have been prepared and studied, as well as pure Me₃M(CMe?CH₂) and mixtures containing propenyl isopropenyl residues bonded to silicon and lead. ¹H, ¹³C, ²⁹Si and ²⁰⁷Pb NMR data are presented; as previously observed for the corresponding tin compounds, the ²⁹Si and ²⁰⁷Pb shifts for the Me₃MC₃H₅ isomers can be used to calculate the shifts expected for the other isomers; while for lead the agreement is good, calculated and observed values for silicon diverge with decreasing n due, at least in part, to steric factors.     

Mass spectrometric investigation of stereosomeric 1,2-dimethyl-4-substituted decahydroquinol-4-ol N-oxides. Concerning the configuration of the asymmetric nitrogen atom

The main fragmentation pathways of the N-1, C-2 and C-4 stereoisomers of the 1,2-dimethyl-4-R-transdecahydroquinoline-4-ol N-oxides (R=C?CH, CH?CH₂ and C₂H₅) under electron impact are discussed. The correlation between the mass spectrometric chromatographic behaviour and the configuration of polar groups in the N-oxides examined is discussed. The mass spectra of the N-1 stereoisomers may be subdivided into two groups, depending only on the orientation of N→O group and not of the 4-OH group. The spectra of N-oxides with the axial N-oxide group reveal less intense ions and much more intense [M? CH₃]⁺, [M? O]⁺, [M? OH]⁺ and ions, whereas in the spectra of their equatorial epimers the abundance of the ions exceeds the intensities of the latter ions.     

Übergangsmetall-substituierte Acylphosphane und Phosphaalkene. 22 [1] Insertionen von Hexafluoraceton in die PX-Bindung von Metallophosphanen des Typs (η5-C5Me5)(CO)2M?PX2 (M = Fe,Ru; X = Me3Si,Cl). Strukturbestimmung von (η5-C5Me5)(CO)2Fe?P(SiMe3)C(CF3)2(OSiMe3)

Transition Metal-substituted Acylphosphanes and Phosphaalkenes. 22. Insertions of Hexafluoroacetone into the PX-Bond of Metallophosphanes (η⁵-C₅Me₅)(CO)₂M? PX₂ (M = Fe, Ru; X = Me₃Si, Cl). Structure Determination of (η⁵-C₅Me₅)(CO)₂Fe? P(SiMe₃)C(CF₃)₂(OSiMe₃) Reaction of the metallophosphanes (η⁵-C₅Me₅)(CO)₂M? P(SiMe₃)₂ ( 1a : M = Fe; 1b : M = Ru) with hexafluoroacetone (HFA) afforded the complexes (η⁵-C₅Me₅)(CO)₂M? P(SiMe₃)C(CF₃)₂(OSiMe₃) ( 2a, b ). The attempted synthesis of a metallophosphaalkene from 2a by thermal elimination of hexamethyldisiloxane failed. The acid catalyzed hydrolysis of 2a afforded compound (η⁵-C₅Me₅) · (CO)₂Fe? P(H)C(CF₃)₂(OSiMe₃) ( 3 ). Hexafluoracetone and (η⁵-C₅Me₅)(CO)₂Fe? PCl₂ ( 4 ) under-went reaction to give the metallochlorophosphan (η⁵-C₅Me₅) · (CO)₂Fe? P(Cl)? O? C(CF₃)₂Cl ( 5 ). Constitutions and configurations of the compounds ( 2–5 ) were established by elemental analyses and spectroscopic data (IR, ¹H-, ¹³C, ¹⁹F-, ²⁹Si-, ³¹P-NMR, MS). The molecular structure of 2a was determined by x-ray diffraction analysis.     

Mass spectra of halogenated esters: 8. Methyl esters of 2,3-dichloro-, bromochloro- and dibromopropenoic acids

The mass spectral fragmentation of methyl esters of E and Z isomers of 2,3-dichloro-, 2-bromo-3-chloro-, 3-bromo-2-chIoro- and 2,3-dibromopropenoic acids have been investigated. The M^+˙ peak is shown with all isomers, the [M ? OCH₃]⁺, [M ? X]⁺, [M ? OCH₃ ? CO]⁺, [M ? OCH₃ ? CO ? X]^+˙ and [M ? OCH₃ ? CO ? X ? X]⁺ ions constituting abundant peaks in all spectra. The results, particularly from the bromochloro isomers, show that a halogen atom is eliminated from the 3- rather than the 2- position and from the Z rather than the E isomer. Bromine as a bulky atom is preferentially lost.     

Translational energy release and stereochemistry of steroids. VII—the loss of angular methyl groups after the dehydration of molecular ions of cholesterol and related C(5)-unsaturated 3β-hydroxy steroids

The translational energy, T, released during the loss of the angular 18- and 19-methyl groups both from metastable molecular ions and metastable [M ? H₂O]⁺ and [M ? 2H₂O]⁺ ions, in C(5)-unsaturated mono-and di-hydroxy steroids, as well as in their 19-nor and deuterated analogues bearing the label in the 19-methyl group, has been measured. It was found that, while the T values for the 19-CH₃ loss, following the dehydration of the molecular ions, are increased substantially when compared to those for the same loss from the molecular ions, the T values for the 18-CH₃ loss are increased much more moderately. Nevertheless, the amounts of translational energy released in the [M ? H₂O]⁺˙ ? 18-CH₃˙ and [M ? 2 H₂O]⁺˙ ? 18-CH₃˙ transitions are still higher than those found for the respective 19-methyl loss, in accordance with the general rule established recently.