Production of organometallic polymers by the interfacial technique. XX. Synthesis of polyoxystannyloxyalkylenes

Polyoxystannyloxyalkylenes of low to intermediate molecular weight were synthesized in low to high yield by a modified nonaqueous interfacial technique. At least some of the products possess Sn? Cl, Sn? OH, and R? OH endgroups. The aqueous stability of the products is in the order neutral ? basic > acidic.     

Darstellung und Eigenschaften von Ti-substituierten N-Heterocyclen

Preparation and Properties of Ti-substituted N-Heterocycles The compounds (x = 2 to 6) have been prepared by transamination of Ti(NMe₂)₄ with the heterocyclic amines and have been characterised by elemental analyses and ¹H NMR and IR spectroscopy. The dependence on both x and n of the thermal decomposition has been studied for the series and . The results can be interpreted in terms of the steric strain of the R₂N and substituents. Apart from the piperidido groups none of the ligands exhibit protective group properties comparable to the R₂N groups.     

Darstellung neuer Spiro-Alkoxy-cyclophosphazatriene

Preparation of New Spiro-Alkoxy-Cyclophosphazatrienes New spiro-Alkoxy-cyclophosphazatrienes of the general formula are described. The preparation of the substances and their mass spectroscopic data are reported.     

Synthesis and psychotropic properties of furyl- and thienyl-germatranes

Trihalogermyl-furans and -thiophenes were prepared by inserting germanium dibromide (GeBr₂) generated from the dibromogermane(II) dioxanate complex into the carbon-halogen bond of halo-furans and -thiophenes. Their ethanolysis and transesterification by triethanolamine yielded the germatranes which were subjected to psychotropic activity assays. The psychotropic properties of germatranes were found to depend on the type of the heterocycle and on the position of the germatrane moiety.     

Kinetics and mechanisms of the reaction of acetylene with cyclohexa-1,3-diene and the decomposition of bicyclo[2.2.2]-octa-2,5-diene in the gas phase

The reaction of acetylene (A) with cyclohexa-1,3-diene (CHD) has been studied between 450 and 592 K. The pressures of A ranged from 25 to 112 torr and those of CHD from 8 to 62 torr. The reaction yields only ethene (E) and benzene (B) instead of bicyclo[2.2.2]octa-2,5-diene (BOD), the product that is expected for a 1,4,1′,2′ addition of the Diels–Alder type. It is first order with respect to each reagent. The rate constant (in L/mol·s) is given by The thermal decomposition of BOD has also been studied. In the ranges of 354–435 K and 0.5–6 torr, the reaction is first order and results in the formation of equal amounts of B and E as the reaction of A with CHD does. Its rate constant (in s^?1) is given by The following consecutive reactions are proposed for the reaction between A and CHD: where BOD is the primary product that is too unstable to be detected. This implies that the rate constant k is equal to k_a. The reaction mechanisms and the strain energy in BOD are discussed.     

Darstellung und Stabilität von Aroxy-fluor-silanen

Preparation and Stability of Aroxy-fluoro-silanes. Different possibilities for preparation of aroxy-fluoro-silanes (esp. substituted phenoxy-fluoro-silanes) are investigated. The reaction was proved as the best method of preparation. The aroxy-fluoro-silanes are disposed to dismutation reactions.     

Massenspektrometrische Untersuchung organischer Stickstoffverbindungen. XXVII—Intramolekulare Redoxreaktionn bei ionisierten ortho-substituierten Nitroaromaten

Collisional activation demonstrates that the stable ions from o-nitrobenzaldehydedimethylacetale possess the structure of ionized o-nitroso benzoic acid methyl ester. Contrary to previous conclusions it is demonstrated that the structure of the stable ions (m/e 135) from different precursors [i.e. o-nitrobenzyl alcohol o-nitrobenzyl cyanide and o-nitrobenzaldoxime is best represented by 2,1-benzisoxazoline-3-one. Ionized o-nitrosobenzaldehtde rearranged to 2,1-benzisoxazoline-3-one prior to collision induced decomposition, whereas 2-benzoxazolinone and 3-hydroxy-1,2-benzisoxazole do not rearrange within 10^?5 s.     

HNO,an Intermediate in (Light-induced) Rearrangement Reactions of Nitrosooxy Compounds and Nitrosamines

IR-spectroscopic investigations of light-induced rearrangement reactions of nitrosooxymethane (CH³ONO³), nitrosooxyethane (CH₃CH₂ONO) and N,N-dimethylnitrosamine ((CH₃)₂NNO) in low-temperature rare-gas matrices have established that these molecules are transformed in two photolysis steps to the previously unknown C-nitroso compounds nitrosomethanol (CH₂(OH)(NO)), 1-nitrosoethanol (CH₃CH(OH)(NO)), and methyl(nitrosomethyl)amine CH₂(NO)(NH)(CH₃). Evidence for a similar rearrangement reaction has been advanced for N-Nitrosopyrrolidine which is converted to C-nitrosopyrrolidine . The matrix-isolation technique in combination with wavelength-selective irradiation allowed to trap and characterize an intermediate of rearrangement which revealed to be nitroxyl (HNO) complex (CH₂…HNO, CH₃CHO…HNO, CH₃N = CH₂…HNO, and ). Since these findings have a close resemblance with rearrangement reactions of more complex nitrosooxy compounds, nitrosamines, or nitrosohydrazines used in organic synthesis, it is suggested that also in these reactions nitroxyl is present as an intermediate species.     

Fluorsulfonylstickstoffverbindungen

The reactions of fluorosulfonylurea derivatives with phosphorus pentachloride in carbon tetrachloride leads to and . These compounds are easily fluroinated by arsenic trifluoride to the corresponding fluorosulfonyl derivatives. It was shown that PCl₅ is reliable for the fluorine-chlorine exchange. Isocyanate esterchlorides as well as carbonyl-fluoride derivatives react with compounds which have an active hydrogen atom. By this way were prepared: . By hydrolysis of , is probably formed as the first reaction product. The acid could be trapped with tetraphenylphosphoniumchloride as a well-cristalline salt. Fluorosulfonyl isocyanate reacts with aldehydes to the following compounds: FSO₂N ? CHCH₃, FSO₂N ? CHC₂H₅, FSO₂N ? CH? CH(CH₃)₂ and FSO₂N ? CHC₆H₅. The physical and chemical properties as well as IR and NMR spectra of the compounds are described and, in part, compared and discussed.     

Thermal decomposition of 3-chloro-3-trichloromethyldiazirine in solution

The thermal decomposition of 3-chloro-3-trichloromethyldizairine in carbon tetrachloride and iso-octane has been investigated over the temperature range 75–115°C. The products, tetrachloroethylene and nitrogen, are formed quantitatively by a first-order reaction which is probably unimolecular: The results yielded the following Arrhenius equations: .     

New telechelic polymers and sequential copolymers by polyfunctional initiator-transfer agents (inifers). XVIII. Epoxy and aldehyde telechelic polyisobutylenes

This article concerns the synthesis and characterization of new epoxy and aldehyde telechelic polyisobutylenes, that is, and . The synthesis of the epoxy derivative was achieved by quantitative epoxidation of α,ω-di(isobutenyl) polyisobutylene with m-chloroperoxybenzoic acid and that of the dialdehyde by quantitative isomerization of the epoxy termini with zinc bromide. Infrared (IR) and ¹H-NMR analysis of these new telechelic polymers and ultraviolet (UV) analysis of the 2,4-dinitrophenylhydrazine derivative of the dialdehyde indicate quantitative conversions and yields, that is, essentially theoretical functionalization (F _n = 1.95 ± 0.05).     

Thermal decomposition of 1,1,2,2-tetramethylcyclopropane in a single-pulse shock tube

1,1,2,2-Tetramethylcyclopropane (TTMC) has been decomposed in a single-pulse shock tube. The main reaction process is Side reactions are unimportant. From comparative rate experiments (with cyclohexene decomposition as standard) the rate expression for these reactions are These numbers are consistent with a «best» value for cyclohexene decomposition of      

Kinetics,mechanism, and endo selectivity of Diels–Alder reactions of alkylmonosubstituted ethenes with cyclohexa-1,3-diene in the gas phase

The reactions where Y = CH₃ (M), C₂H₅ (E), i? C₃H₇ (I), and t? C₄H₉ (T) have been studied between 488 and 606 K. The pressures of CHD ranged from 16 to 124 torr and those of YE from 57 to 625 torr. These reactions are homogeneous and first order with respect to each reagent. The rate constants (in L/mol·s) are given by The Arrhenius parameters are used as a test for a biradical mechanism and to discuss the endo selectivity of the reactions.     

Some new examples of cationic polymerization

Synthesis and properties of cis-and trans-methoxyvinyl chloride (MVC) are described. Both of these monomers can be polymerized with cationic initiators. From the ¹³C-NMR spectra it was concluded, that poly-(trans-MVC) is mainly threo-diisotactic. Copolymerization of cis-MVC with for instance trans-MVC or styrene or 1,3-dioxolane is also described. The ring-opening polymerization of 2-phenyl-2-oxazoline under different conditions was investigated. The molecular weights, determined by light-scattering and GPC are in the range between 10 000 and 350 000. A[η] -M- equation was derived. By hydrolysis with hydrochlorid acid high molecular weight poly(iminoethylene) was obtained. The ring-opening polymerization of 1-azabicyclooctane [4.2.0] (conidine) with different catalysts as well as the properties of the polymers were studied in detail. By means of a “mixed-mechanism technique” well defined styrene-conidine diblock copolymers are available.     

A New Strategy to Exfoliate Silicone Rubber/Clay Nanocomposites

Summary: A new strategy was developed to prepare disorderly exfoliated nanocomposites, in which a soft siloxane surfactant with a weight‐average molecular weight ( ) of 1 900 was adopted to modify the clay. The modified clay slurry was then mixed with silicone rubber by hand, and exfoliation was achieved. The proposed mechanism thereof was verified by TEM and XRD. The physical entanglement of the soft siloxane surfactant plays a vital role in the diffusion and intercalation of the matrix molecules during the compounding of the slurry‐polymer mixture. This simple method is applicable to other silicone‐based materials reinforced by clay.

TEM micrograph of silicone rubber/clay‐sil nanocomposite.     

Amino-phosphane. X. Einige Additionsreaktionen von N-Diphenylphosphinotetraphenyldiphosphin-imid

Diphenylphosphorous chloride and methyl iodide add readily to the N-bonded P(III)-atom of (C₆H₅)₂P? P(C₆H₅)₃?N? P(C₆H₅)₂ forming the salts [(C₆H₅)₂P? P(C₆H₅)₂ N P(C₆H₅)₂? P(C₆H₅)₂]Cl and [(C₆H₅)₂P? P(C₆H₅)₂ N P(C₆H₅)₂. CH₃]I, respectively. A similar behaviour is observed with sulfur: Under mild conditions (C₆H₅)₂P? P(C₆H₅)₂?N? P(C₆H₅)₂ = S is formed but forcing conditions are required to produce S = P(C₆H₅)₂? P(C₆H₅)₂?N? P(C₆H₅)₂?S. The monosulfide is also obtained by treating (C₆H₅)₂P(S)N[Si(CH₃)₃]₂ with diphenylphosphorous chloride, indicating the favoured formation of the phosphazene system as compared with the phosphazane system Confirmation of the structures comes from ³¹P nmr and IR data, and for the sulfides also from their degradation with bromine.     

Effect of gegen ion in cationic polymerization and copolymerization of trioxane

p-Chlorophenyldiazonium hexafluorophosphate has been reported to be a superior catalyst for cationic polymerization and copolymerization of trioxane as compared to boron trifluoride dibutyl etherate (BF₃·Bu₂O)¹. In the present investigation the effect of anions derived from elements in Group VA, AsF and SbF, has been ascertained. It has been concluded that p-chlorophenyldiazonium hexafluoroarsenate is also a superior catalyst to boron trifluoride dibutyletherate (BF₃·Bu₂O), while p-chlorophenyl-diazonium hexafluoroantimonate is inferior. Copolymers with the highest polymer yield (>95%) and molecular weight (intrinsic viscosity = 4 to 5) were obtained with Simple dependences on catalyst concentration have been observed to hold for a wide catalyst concentration range ([M]/[C]) = (1 to 20) × 10⁵: For the same relationships hold. However, the polymer yield (75%) and molecular weights (intrinsic viscosity ?1) are considerably lower while the extent of chain transfer is higher. Furthermore, the polymerization proceeds with explosive violence. The quantitative aspects resulting from polymerization, for the most part, can be interpreted in terms of the extent of dissociation of the propagating ions.     

Synthese „anorganischer”︁ Tintenfisch-Moleküle

Inorganic Pode-Type Molecules The reaction of monosubstituated polyethylenglykoles [m = 0—4, R = Cl, OCH₃, OAs(CH₃)₂, OSi(CH₃)₃] with amino compounds (CH₃)_xE[N(CH₃)₂]_y(E = Si, x = y = 2; E = Si, x = 1, y = 3; E = P, x = 0, y = 3; E = As, y = 0, y = 3) results in the formation of pode-type molecules of the formula . The synthesis and rearrangement of these compounds by heating is described.     

Thermal decomposition of ammonia in shock waves

The thermal decomposition of ammonia was studied by means of the shock-tube and vacuum ultraviolet absorption spectroscopy monitoring the concentration of atomic hydrogen. The rate constants of both the initiation reaction and the consecutive reaction were determined directly as and respectively.