Fluorierung von Dioxa- und Oxazaphospholanen

Fluorination of Dioxa- and Oxazaphospholanes The fluoridolysis of cyclic esters and esteramides of phosphorous acid ( 1 , 2 , 4 , 5 , 7 , 11 , and 12 ,) using the acid fluorination reagent Et₃N · nHF (n > 1) or an excess of a basic composed agent (n < 1) yields in all cases HPF₅^? ( 3 ,). With stoichiometric amounts of fluoride, however, the fluorophospholanes ( 4 ,) and ( 5 ,) as well as fac.- and mer.-o- ( 6a, 6b ,) and the spirocyclic fluorohydridophosphate ( 8 ,) are obtained. ( 13 ,) reacts to ( 14 ,) and the spirocyclic compound ( 15 ,) gives ( 16 ,). The fluorophosphoranes ( 18 ,), ( 19 ,), and ( 21 ,) are obtained by oxidative fluorination of the spiro- or bicyclic P? H compounds 11, 12 , and 20 , with CCl₄/Et₃N · nHF (n < 1). The oxidative fluorination of the cyclic triesters of phosphorous acid 7 , and 23 , leads to the cyclic fluorophosphates ( 22 ,) and 16 , as well as 6. , The compounds 18, 19 , and 22 , are also formed by oxidative fluorination of elemental phosphorus, P₄, in the presence of the corresponding bifunctional nucleophile.     

13C NMR spectra of 2,3-dihydro-1H-pyrrolo[1,2-c]imidazol-1,3-dione and its thione analogues

Analysis of the ¹³C NMR spectra of a series of 2,3-dihydro-1H-pyrrolo[1,2-c]imidazole derivatives has provided chemical shift data for (?184 ppm), (?173.5 ppm), (?158 ppm) and (?148 ppm) groups. A full analysis of the ¹³C chemical shifts of the C atoms of the pyrrole ring and of an N-phenyl substituent is described.     

Perfluorovinyl Morpholine and Perfluorovinyl Pyrrolidine with Nucleophiles and Electrophiles

In this study, both monofunctional and bifunctional nucleophiles, as well as the electrophile FNO, are reacted with perfluorovinyl amines. The perfluorovinyl amines CF?CF₂ and CF?CF₂ have been reacted with dimethylamine and diethylamine in the presence of small amounts of water to give CHFC(O)N(CH₃)₂ ( 1 ), CHFC(O)N(CH₃)₂ ( 2 ), and CHFC(O)N(C₂H₅)₂ ( 3 ). With perfluorovinyl pyrrolidine and perfluorovinyl morpholine, ethanolamine gives the cyclized products CHF ( 4 ) and CHF ( 5 ), respectively. Reaction of the vinyl amines with (CH₃)₃SiOCH₂CF₃ in the presence of catalytic amounts of CsF results in the formation of cis- ( 6 ) and trans- ( 7 ) CF?CF(OCH₂CF₃) and cis- ( 8 ) and trans- ( 9 ) CF?CF(OCH₂CF₃). The electrophile FNO reacts slowly with perfluorovinyl pyrrolidine and perfluorovinyl morpholine, and more rapidly with (CF₃)₃CCF?CF₂ to give CF(NO)CF₃ ( 10 ), CF(NO)CF₃ ( 11 ) and (CF₃)₃CF(NO)CF₃ ( 12 ), respectively. Single crystal X-ray analysis is used to confirm the identity of the product obtained from the controlled hydrolysis of the sultone of perfluorovinyl pyrrolidine as the sulfonic acid anhydride C(O)CF₂OS(O)₂OCF₂C(O) ( 13 ). The X-ray crystal structure of perfluorosuccinic acid monohydrate ( 14 ), which is obtained when the perfluorovinyl pyrrolidine sultone is hydrolyzed in excess water, is also reported for the first time.     

Beiträge zur Komplexchemie der Phosphine und Phosphinoxide,XXVIII. Übergangsmetall-aminoalkylphosphin-Komplexe Teil 2: Palladium- Und Platinkomplexe

On the Coordination Chemistry of Phosphines and Phosphine Oxides. XXVIII. Transition Metal Aminoalkylphosphine Complexes. Part II: Palladium and Platinum Complexes Aminoalkylphosphines – C₆H₅HP? CH₂ · CH₂? , (C₆H₅)₂P? CH₂ · CH₂ · CH₂? NH₂, (C₆H₅)₂P? CH₂ · CH₂ · CH₂? N?CHC₆H₅ – react with palladium and platinum salts to give coordination compounds of the type MX₂, MX₂()₂, and MX₂()₄ (M = Pd, Pt; X = Cl, BPh₄). The chelating activity of the ligands, structure and properties of the metal complexes are discussed.     

Lösungsthermodynamik von FeCl2 in Mischschmelzen aus Alkalichloriden und LaCl3 bzw. CeCl3

Solution Thermodynamics of FeCl₂ in Molten Mixtures of Alkaline Chlorides and LaCl₃ or CeCl₃ Activity coefficients and the chemical excess potential of FeCl₂ dissolved in molten chloride mixtures were determined by EMF measurements with galvanic cells of the type in the concentration range from 0.01–5 mole-% at 720 and 820°C. An average cationic potential is defined and used to calculate a distance parameter () for the different solvent melt mixtures. may be estimated by equations of the type      

Electric conductivity of polymer composites with 7,7,8,8-tetracyanoquinodimethan salts

The electric properties of polymer composites with highly conductive 7,7,8,8-tetracyanoquinodimethan (TCNQ) salts such as quinolinium–TCNQ complex salt (), acridinium–TCNQ complex salt (), and N-methylacridinium–TCNQ complex salt () were studied. Polyacrylonitrile (PAN), poly(N-vinylcarbazole) (PVK), and poly(4-vinylpyridine), (P4VP), etc., were chosen as matrix polymers. The resistivity (ρ) of the was 0.37 Ω cm at the content of 20 wt % in the film. When the content of was increased up to 40 wt%, a phase separation of the needle crystals was observed and the ρ value increased. When was dispersed into PAN or PVK, the separation was also observed and the samples showed low conductivity. The uniform films were obtained in the and systems, but the values of ρ were high because of the degradation of the TCNQ salts. Uniform films with the naked eye were obtained in the and systems, and the values of Ω were 0.37, 1.05, and 3.40 Ω cm, respectively. was stable even when dispersed into P4VP. The properties of the composites were influenced by the combination of the TCNQ salts and the polymers. The uniformity and the stability of the composites were necessary to obtain the high conductive composites.     

Effects of Non-planarity in the Radical Anions of Tribenzo[a,c,e]cyclooctenes

Reduction of tribenzo[a,c,e]cyclooctene ( 2 ) and its 2,3- and 1,4-dimethyl derivatives ( 4 and 5 ), as well as of 1,1-dimethyl-10,11-propane-2,2-diylidene-1H-benzo[5,6]cycloocta[1,2,3,4-def]fluorene ( 6 ) and its 5,6-didehydro derivative ( 7 ) was followed by cyclic voltammetry. The radical anions of these compounds and those of their derivatives (D) 2 , (D) 5 , and (D) 6 , deuteratsd at C(9) in 1 and 5 or in the corresponding position of 6, have been characterized with the use of ESR, ENDOR, and TRIPLE-resonance spectroscopy. The cyclic-voltammetric and proton-hyperfine data are consistent with the increasing deviations of the radical anions from planarity in the order These deviations, due to steric or interferences in the peri-positions 1?14 and 4?5, are removed in and by the introduction of bridging groups. The non-plalarity affects the thermodynamic and kinetic stabilities of the radical anions and causes a shift in the π-spin distribution away from that benzene ring which is linked to the two others by the essential single bonds C(4a)? C(4b) and C(14a)? C(14b). This finding suggests that the steric hindrance in , and is alleviated by twisting this ring out of coplanarity with the remaining (Z)-stilbene-like π-system.     

Rearrangement of the Radical Anions of 1,6-Bridged[10]Annulenes to Derivatives of 5H-Benzocycloheptene and Benzotropylium

The rearrangement products obtained upon reduction of 1,6-methano[10]-annulene ( 1 ) and its 11-halogen derivatives have been studied by ESR. and, in part, by ENDOR. spectroscopy. These derivatives comprise 11,11-difluoro- ( 2 ), 11-fluoro- ( 3 ), 11,11-dichloro- ( 4 ) and 11-bromo-1,6-methano[10]annulene ( 5 ), as well as the 2,5,7,10-tetradeuteriated compounds 2 -D₄ and 3 -D₄. The studies of the secondary products in question have been initiated by the finding that the radical anion of 11,11-dimethyltricyclo[4.4.1.0^1,6]undeca-2,4,7,9-tetraene ( 12 ), i.e., the prevailing valence isomer of 11,11-dimethyl-1,6-methano[10]annulene, undergoes above 163 K a rearrangement to the radical anion of 5,5-dimethylbenzocycloheptene ( 14 ). A rearrangement of this kind also occurs for the radical anion of the parent compound 1 , albeit only above 323 K. The lower reactivity of 1 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} relative to 12 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} is rationalized by the assumption that the first and rate determining step in the case of 1 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} is the valence isomerization to the radical anion of tricyclo[4.4.1.0^1,6]undeca-2,4,7,9-tetraene ( 1a ). In the reducing medium used in such reactions (potassium in 1,2-dimethoxyethane), the final paramagnetic product of 1 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} is not 5H-benzocycloheptene ( 15 ), but the benzotropylium radical dianion ( ). This product ( ) is also obtained from the radical anions of the halogen-substituted 1,6-methano[10]annulenes, 2 to 5 , in the same medium. The temperatures required for the conversion of 2 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} and 3 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} into lie above 293 and 243 K, respectively, whereas the short-lived species 4 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} and 5 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} undergo such a rearrangement already at 163 K. The stability of the four halogen-substituted radical anions thus decreases in the sequence 2 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} > 3 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} > 4 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} ≈ 5 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document}. Replacement of 2 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} and 3 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} by 2 -D₄\documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} and 3 -D₄\documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document}, respectively, leads to 1,4,5,8-tetradeuteriobenzotropylium radical dianion ( ). Experimental evidence and theoretical arguments indicate that the rearrangements in question are initiated by a loss of one ( 3 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} and 5 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document}) or two ( 2 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document} and 4 \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document}) halogen atoms. Such a reaction step must involve the intermediacy of the radical 19 · (see below) which rapidly isomerizes to the benzotropylium radical 16 :. Support for the transient existence of 19 . is provided by the thermolysis of 1,6-methano [10]annulene-11-t-butylperoxyester (6) which yields 16 . in a temperature dependent equilibrium with a mixture of its dimers ( 16 ₂). In the hitherto unreported ESR. spectra of 2\documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document}. and 3\documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}} $\end{document}, the coupling constants of the ring protons differ considerably from the analogous values for the radical anions of other 1,6-bridged [10]annulenes. These differences strongly suggest that the fluoro-substitution substantially affects the character of the singly occupied orbital.     

Rearrangements of Radical Cations of [2.2]Paracyclophanes and of a bridged [14]annulene to those of pyrenes: An ESR and ENDOR study

ESR and ENDOR studies have been carried out on the radical cations obtained consecutively by reaction of trans-10b, 10c-dimethyl-10b, 10c-dihydropyrene ( 4 ) with AlCl₃ in CH₂C1₂. The primarily formed ${\bf 4}^{+ \atop \dot{}}$ rearranges at 253 K to the radical cation(s) of 1,6- ( 5a ) and/or 1,8-dimethylpyrene ( 5b ). At 323 K, the spectra of ${\bf 5a}^{+ \atop \dot{}}$/${\bf 5b}^{+ \atop \dot{}}$ are replaced by that of the highly persistent radical cation of 1,3,6,8-tetramethylpyrene ( 6 ). Surprisingly, ${\bf 6}^{+ \atop \dot{}}$ is also the only observable paramagnetic product resulting from a treatment of 4,5,7,8- ( 1 ), 4,7,13,16- ( 2 ), and 4,5,12,13-tetramethyl[2.2]paracyclophane ( 3 ) with AlCl₃ in CH₂Cl₂ at 353 K. The structures of the intermediates in the rearrangement [${\bf 1}^{+ \atop \dot{}}$, ${\bf 2}^{+ \atop \dot{}}$, ${\bf 3}^{+ \atop \dot{}}$] → ${\bf 6}^{+ \atop \dot{}}$ are discussed.     

Beiträge zur Chemie der Oxidhalogenide von Molybdän und Wolfram. V. Molybdänoxidtetrachlorid und Molybdänoxidtrichlorid

The formation enthalpies were ascertained from the solution enthalpies in 2 n NaOH resp. 2 n NaOH + 1% H₂O₂. The results of equilibrium measurements in the systems give the formation enthalpies and standard entropies: . The value of the standard entropy of the gaseous MoOCl₄ was estimated to be 91 (±3) cl. From the enthalpies and entropies of sublimation the values were obtained.     

Radical Ions of a Bishomobinaphthylene Containing two 1,6-methano[10]annulene moieties: An ESR and ENDOR study

The radical cation and the radical anion of ‘syn’-cyclobuta[1,2-c:3,4-c′]di-1,6-methano[10]annulene (‘syn’-4a,12a:6a, 10a-bishomobinaphthylene; 3 ) have been characterized by their hyperfine data. The highly resolved ESR spectrum of $ 3^{+ \atop \dot{}} $ is dominated by a triplet splitting from the outer pair of methano β-protons (H_o). In contrast, the ESR spectrum of $ 3^{- \atop \dot{}} $ is poorly resolved with the largest coupling constants arising from perimeter α-protons. The different hyperfine features of $ 3^{+ \atop \dot{}} $ and $ 3^{- \atop \dot{}} $ are rationalized by MO models. The SOMO of $ 3^{+ \atop \dot{}} $ ψ_SA(b₁), has substantial LCAO coefficients of the same sign at the bridged atoms C(1), C(6), C(11), and C(16), whereas in the SOMO of $ 3^{- \atop \dot{}} $, ψ_SS(a₁), the four atoms lie in the vertical nodal planes. The large width and the reluctance to saturation of the lines in the ESR spectrum of $ 3^{- \atop \dot{}} $ are attributed to the near-degeneracy of the lowest antibonding MO's. Due to their similar nodal properties, the SOMO's of $ 3^{- \atop \dot{}} $ and the radical anions of binaphthylene ( 4 ), 1,6-methano[10]annulene ( 1 ), and naphthalene ( 2 ) are interrelated. Moreover, because the cyclic π-systems in 3 and 1 deviate in the same way from planarity, the effect of such distortions on the coupling constants, a_Hμ, of the perimeter α-protons in $ 3^{- \atop \dot{}} $ and $ 1^{- \atop \dot{}} $ should be comparable. Indeed, on going from $ 4^{- \atop \dot{}} $ to $ 3^{- \atop \dot{}} $, the |a_Hμ| values are reduced exactaly by half as much as the corresponding values on passing from $ 2^{- \atop \dot{}} $ to $ 3^{- \atop \dot{}} $, of which the cyclic π-systems are twice contained in $ 4^{- \atop \dot{}} $ and $ 3^{- \atop \dot{}} $ respectively.     

The Electronic Structure of Pentaprismane (C10H10), as Revealed by its Photoelectron Spectrum

The photoelectron (PE.) spectrum of the title compound has been assigned by comparison with the PE. spectrum of cubane ( 2 ), aided by ab initio STO-3G calculations using localized molecular orbitals. On the basis of the information available to date, the most satisfactory orbital sequence, Koopmans theorem implied, is, in descending order of energy: band system : (2e″₂, 3e′₂ 2e″₁, 3e′₁); band system : 3a′₁ (2e′₂, 2a″₂); band : 2e′₁.(Sequence of orbitals in parenthesis uncertain).     

Über die oxidative Fluorierung von (CF3)(R) (R = CF3, Cl) und die Kristallstruktur von (CF3)(Cl)F+ AsF6−

Oxidative Fluorination of (CF₃)(R) (R = CF₃, Cl) and the Crystal Structure of (CF₃)(Cl) F⁺ AsF₆^? Oxidative fluorination of (CF₃)(R) (R = CF₃, Cl) with XeF⁺MF₆^? (M = As, Sb) in anhydrous HF results in formation of monofluorsulfonium hexafluorometalates. The salts are characterized by vibrational, NMR, and mass spectra. (CF₃)(Cl)F⁺ AsF₆^? crystallizes in the monoclinic space group P2₁/c with a = 9.955(10) Å, b = 11.050(5) Å, c = 12.733(15) Å, β = 97.77(5)°, and Z = 4.     

Kinetics and the mechanism of the thermal reaction between trifluoromethylhypofluorite and hexafluoropropene

The kinetics of the thermal reaction between CF₃OF and C₃F₆ have been investigated between 20 and 75°C. It is a homogeneous chain reaction of moderate length where the main product is a mixture of the two isomers 1-C₃F₇OCF₃ (68%) and 2-C₃F₇OCF₃ (32%). Equimolecular amounts of CF₃OOF₃ and C₆F₁₄ are formed in much smaller quantities. Inert gases and the reaction products have no influence on the reaction, whereas only small amounts of oxygen change the course of reaction and larger amounts produce explosions. The rate of reaction can be represented by eq. (I): The following mechanism explains the experimental results: Reaction (5) can be replaced by reactions (5a) and (5b), without changing the result: Reaction (4) is possibly a two-step reaction: For ∣CF₃ = ∣C₃F₆∣, ν_20°C = 36.8, ν_50°C = 24.0, and ν_70°C = 14.2.     

Über Chalkogenolate. 121. Untersuchungen über N-Cyanomonothiocarbimidsäure 1. Darstellung und Eigenschaften von Alkalimetall-N-cyanomonothiocarbimaten

On Chalcogenolates. 121. Studies on N-Cyanomonothiocarbimic Acid. 1. Synthesis and Properties of Alkali Metal N-Cyanomonothiocarbimates The hitherto unknown N-cyanomonothiocarbimates M₂[SOC?N? CN] · H₂O, where M = Na, K, Rb, Cs, have been prepared by reaction of the corresponding alkali metal salt of cyanamide with COS. N-Cyanomonothiocarbimates react with sulfur to form the ion, which gives with an acid and with CH₃I the methyl compound . The reaction of the latter compound with H₂O₂ yields . All compounds have been characterized by means of diverse methods.     

The gas phase ion chemistry of the acetyl cation and isomeric [C2H3O]+ ions. On the structure of the [C2H3O]+ daughter ions generated from the enol of acetone radical cation

Methods are described for the unequivocal identification of the acetyl, [CH₃? \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document} ?O] (a), 1-hydroxyvinyl, [CH₂?\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}? OH] (b), and oxiranyl, (d), cations. They involve the careful examination of metastable peak intensities and shapes and collision induced processes at very low, high and intermediate collision gas pressures. It will be shown that each [C₂H₃O]⁺ ion produces a unique metastable peak for the fragmentation [C₂H₃O]⁺ → [CH₃]⁺+CO, each appropriately relating to different [C₂H₃O]⁺ structures. [CH₃? \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}?O] ions do not interconvert with any of the other [C₂H₃O]⁺ ions prior to loss of CO, but deuterium and ¹³C labelling experiments established that [CH₂?\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}? OH] (b) rearranges via a 1,2-H shift into energy-rich leading to the loss of positional identity of the carbon atoms in ions (b). Fragmentation of b to [CH₃]⁺+CO has a high activation energy, c. 400 kJ mol^?1. On the other hand, , generated at its threshold from a suitable precursor molecule, does not rearrange into [CH₂?\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}? OH], but undergoes a slow isomerization into [CH₃? \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}?O] via [CH₂\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}HO]. Interpretation of results rests in part upon recent ab initio calculations. The methods described in this paper permit the identification of reactions that have hitherto lain unsuspected: for example, many of the ionized molecules of type CH₃COR examined in this work produce [CH₂?\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}? OH] ions in addition to [CH₃? \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}?O] showing that some enolization takes place prior to fragmentation. Furthermore, ionized ethanol generates a, b and d ions. We have also applied the methods for identification of daughter ions in systems of current interest. The loss of OH^˙ from [CH₃COOD]^+˙ generates only [CH₂?\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}? OD]. Elimination of CH₃^˙ from the enol of acetone radical cation most probably generates only [CH₃? \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm C}\limits^{\rm + } $\end{document}?O] ions, confirming the earlier proposal for non-ergodic behaviour of this system. We stress, however, that until all stable isomeric species (such as [CH₃? \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm O}\limits^{\rm + } $\end{document}?C:]) have been experimentally identified, the hypothesis of incompletely randomized energy should be used with reserve.     

Thermal stability of alcohols

3,3-Dimethylbutanol-2 (3,3-DMB-ol-2) and 2,3-dimethylbutanol-2 (2,3-DMB-ol-2) have been decomposed in comparative-rate single-pulse shock-tube experiments. The mechanisms of the decompositions are The rate expressions are They lead to D(iC₃H₇? H) – D((CH₃)₂(OH) C? H) = 8.3 kJ and D(C₂H₅? H) – D(CH₃(OH) CH? H) = 24.2 kJ. These data, in conjunction with reasonable assumptions, give and The rate expressions for the decomposition of 2,3-DMB-1 and 3,3-DMB-1 are and      

The He 584 Å Photoelectron Spectra of Analoga of Thiathiophthene

The photoelectron spectra of the four oxygen and nitrogen analogs of thiathiophthene 1 to 4 are reported and discussed. The first two bands are assigned to ionization from the π- and n-molecular orbitals on the basis of CNDO/2 calculations. The assignment of bands and to ionization from π-molecular orbitals is suggested.     

Computer-simulated ESR spectra of irradiated poly(olefin oxides)—effect of glass transition temperature on the ESR spectra

Investigations on the effects of γ irradiation on poly(methylene oxide) (POM) and poly(ethylene oxide) (PEO) have been made employing electron spin resonance (ESR) spectroscopy. The ESR sextet and doublet spectra, recorded for POM and PEO, respectively, on irradition in air at room temperature are broadened as the temperature is lowered and show a reversible change in line shape with temperature. The spectra are analyzed by computer simulation, employing Lorentzian line-shape functions and the least-squares method of total curve fitting. The component spectra are evaluated and are assigned. Superposition of the component quartet, triplet, and doublet spectra, corresponding to the radicals ?H₃, ?H₂O , and O?HO , respectively, together with a singlet due to the radicals ?CH₂ is considered to be the best fit to the observed spectrum for POM. The doublet spectrum recorded for PEO has been assigned to the radicals ?HO . The reversible broadening of the spectra has been associated with the mechanism of molecular motions around the glass transition temperatures of these polymers.     

The radical anion of 1,2:9,10-dibenzo[2.2]paracyclophane.. An ESR,ENDOR, and TRIPLE resonance study

The radical anion of 1,2:9,10-dibenzo[2.2]paracyclophane ( 3 ) has been studied by ESR, ENDOR, and TRIPLE resonance spectroscopy under a variety of experimental conditions. The coupling constants of the eight protons in the deck-benzene rings, and of the four inner and four outer protons in the side-benzene rings are 0.234, 0.123, and 0.036 mT, respectively (solvent: 1,2-dimethoxyethane; counterion: K⁺). All three values have the same sign which is predicted to be negative. Comparison of the largest coupling constant (0.234 mT) with the corresponding value (0.297 mT) for the radical anion of the parent [2.2]paracyclophane ( 1 ) points to similar nodal properties of the singly occupied orbitals in and . Notwithstanding this similarity, seems to associate less readily than with alkali metal counterions, since tight ion pairs of with K⁺ are formed only in solvents of low solvating power. Effects of conformational changes on the ESR spectra, such as those previously observed for the radical anion of [2.2]paracyclophane-1,9-diene ( 2 ), are not apparent for in the temperature range of investigation. Hyperfine data are also reported for the radical anion of a derivative 4 which has a CH₃ substituent in one of the side-benzene rings of 3 .