Preparation and reactions of trifluoromethyl-sulfur oxide nitride

In the reaction of CF₃SOCl with NaN₃ or (CH₃)₃SiN₃, azide, CF₃SON₃ (I) is formed:

Upon gentle warming to room temperature, (I) decomposes under evolution of N₂ to give CF₃SON (II),

which however oligomerizes instantaneously, The monomeric nitride(II) can be captured in the presence of reactive halogene compounds to yield N-substituted trifluoromethan-imino sulfonyl chlorides. With CH₃CN, a six-membered ring compound is obtained:

     

The preparation of fluxional tetrahydrides, (R  H or Me) and their reactions with CO,ButNC or HBr

The cyclometallated monohydrides

(R  H or Me) react with NaOPrⁱ/PrⁱOH/H₂ to give fluxional tetrahydrides, probably

. These are highly fluxional having magnetically equivalent hydridic hydrogens, even at ---100°C. When treated with HBr,

, gives

and with CO it gives a mixture of complexes which are probably

(2 isomers) and

. When treated with Bu^tNC this tetrahydride undergoes similar reactions but another (major) product is formed which appears to be binuclear and fluxional and is probably of type

, with four bridging hydrogens.     

Some chlorine fluorosulfonate and peroxydisulfuryl-difluoride reactions

Chlorine fluorosulfonate adds exceptionally easy not only to various alkenes, perfluorobenzene, but to alkynes too

The addition of peroxydisulfuryldifluoride to alkyl- and perfluoroalkyliodides leads to unstable adducts, which decompose with the formation of alkylfluorosulfonates and iodine fluorosulfonate; the latter was trapped with fluoroalkenes

The use of ClOSO₂F allows to substitute selectively for the fluorosulfonate group the chlorine atom in monochloroacetic acid esters as well as the fluorine atom in hexafluoroacetone N-fluoroimine

ClOSO₂F serves as an exceptionally active chlorinating reagent for fluorinated alcohols, nitrosocompounds, perfluoroacid amides and particularly for benzene

The reaction of (OSO₂F)₂ with perfluoroacid amides leads to the corresponding N,N-bis(fluorosulfonate)amides, which easily rearrange into alkylfluorosulfonates

The hypochlorites of fluorinated alcohols are stable enough and they, similarly to ClOSO₂F, are able to add to alkenes, fluoroalkenes (but not to perfluoroisobutylene), bis(trifluoromethyl)ketene, trifluoromethylisocyanate and perfluoronitriles

The fluorosulfonatoacetic acid esters are unstable at the ambient temperature, but they can be widely used in situ as a very effective alkylating reagents

     

A direct synthesis of 1,3-bis(bromomagnesio)propane

Careful addition of 1,3-dibromopropane

to magnesium in Et₂O yields 1,3-bis(bromomagnesio)propane

which is purified via “magnesacyclobutane”

. Reactions of

with H₂O, CO₂, HgBr₂ and Me₃SnCl are reported. MgBr₂ catalyses the decomposition of

to allylmagnesium bromide

.     

Umsetzung von amino-aziminen mit basen

Amino-azimines of type (1) react at room temperature with bases (ammonia, aliphatic amines, hydrazine and methyl-hydrazine, aqueous/ethanolic sodium hydroxide) by cleavage of the

to the

and the NNN moieties (azide).     

Laser flash photolysis of iodine-iodide mixture in hydroxylic solvent. Evidence for the existence of the radical anion I

The laser flash photolysis of iodine-iodide mixtures in alcoholic solvents produces transient species absorbing in the red and near infrared region with maxima at 740 and 590 nm. The 740 nm absorption band has already been attributed to the well known I

ion. In this work the 590 nm absorption band is assigned to the I

radical anion which presumably could be formed by the equilibrium reaction: I

+ I₃^- ? I

. The variations of the intensities of the 590 and 740 nm transient absorption bands as a function of I₃^? concentration, temperature and solvent, support this assignment. The kinetics of formation of I

and I

has been studied in solutions of tertiary butanol. An analysis of the experimental results shows that the I

ion could be formed via a mechanism involving an I

intermediate.     

Determination de l'enthalpie de formation standard du tetrafluorure de tellure par calorimetrie de combustion dans le fluor et par calorimetrie de reaction

The standard enthalpy of formation of tellurium tetrafluoride has been determined: by combustion in fluorine:

by reaction in a normal solution of soda:

     

Synthese de la phenyl-2-dimethyl-4,5-phosphorine a partir du benzyl-1-dimethyl-3,4-phosphole

1-Benzyl-3,4-dimethylphosphate

-$\text{1}$ is converted into 2-phenyl-4,5-dimethyl-λ₃-phosphorin

-$\text{2}$ through 1,2-dihydro-λ₅-phosphorines

$\text{3}$ and

$\text{s}$.     

ESR spectra and electronic structure: some recent examples.

Results of ESR studies are presented for a number of radical ions selected from several classes of compounds of current interest. The strikingly different hyperfine data for the radical cations of 1,6:8,13-propane-1,3-

and 1,6:8,13-ethane-diylidene-[14]annulene

demonstrate the effect of an interplay of homoconjugative, inductive and hyperconjugative perturbations. The unusually stable radical cations of N,N′-dimethyl-

and N,N′-trimethylene-1,6:8,13-bisimino[14]annulene

should be regarded as N-centered radicals with an N-N 3-electron σ-bond. Despite similar geometries of [2.2]paracyclophane

, its 1,1,2,2,9,9,10,10-octa-fluoro-derivative

and its 1,9,-diene

, the corresponding radical anions strongly differ in their electronic structure. An unexpected conformatinal interconversion is observed for the radical anion of

. Electron acceptors, such as tetracyanoquinodimethane (TCNQ;

) and its areno analogues, and electron donors, represented by tetrathiafulvalene (TTF;

) and compounds containing the TTF system, form salts exhibiting high electronic conductivity (“organic metals”). ESR spectra of the radical anions and trianions of these acceptors and the radical cations of these donors provide detailed information about the spin distribution in the respective species.     

Doping-addition of arylsulfenyl chlorides to the tricyclo[4,2,2,02,5]deca-3,7,9-triene system: skeletal rearrangements and serendipitious products

“doping-addition” of 2-NO₂C₆H₄SCl to the tricyclo[4,2,2,0^2,5]deca-3,7,9-triene system

occurs to give unusual products: (i) rearranged caged cyclopropane

and (ii) the stable cross-perchlorate

.     

Diversity of the gramicidin a spatial structure: two-dimensional 1H nmr study in solution

Theoretical consideration reveals a unique relationship between NMR spectral parameters and possible types of the gramididin A spatial structure. By means of two dimensional NMR spectroscopy four distinct species were detected simultaneously in ethanol solution. Comparison of experimental data and theoretical conclusions demonstrates that species 1 and 2 are left-handed parallel double helices

differing in relative arrangement of the two polypeptide chains within the dimers, species 3 is left-handed antiparallel double helix

, and species 4 is a mirror image of species 1, i.e. right-handed parallel double helix

. The results are compared with those on spatial structures of the peptide in complex with cesium (right-handed antiparallel double helix

) and of the gramicidin A transmembrane ionchannel (N-terminal to N-terminal single-stranded dimer

).     

Excited-neutral-metastable SO2 formation in the , O3-olefin-SO2, and active nitrogen-SO2 systems

Long-liied (τ > 10^?3 s), electronically-excited (E * > 4 eV) neutral metastables, whose formation was attributed to the presence of SO₂, were observed in the three titled systems. Their possible identity as collisionally-accessed metastable states of the normal

, cyclic

, or superoxide

isomers of SO₂ is discussed.     

Synthesis and intramolecular charge-transfer interaction of o-tropyliobiphenyl tetrafluoroborates

A series of o-tropyliobiphenyl tetradfluoroborates

has been synthesized. Evidences are presented to show that

exhibit strong intramolecular charge-transfer interaction between tropylium ion and remote aryl ring. The structure of

was determined by single crystal X-ray diffraction study.     

Especes multiliees dans la chimisorption de co (Ni/Si O2, Ni/Al2O3, Co/Al2O3, Co,Pd/SiO2)

The application of chemical trapping to chemisorbed CO has led to the characterization of multibonded species

on Ni/SiO₂, Ni/Al₂ O₃ , Co, Co/Al₂O₃ and of a bridged form

on Pd/SiO₂. A structure like

[proposed by Muetterties) is in good agreement with infrared and magnetic studies of CO chemisorption on Ni/SiO₂.     

Sussex-N.P.L. computer analysed thermochemical data: Organic and organometallic compounds : J.B. Pedley and J. Rylance,University of Sussex, 1977 £10.00

The formation of new

intermediates and especially germaimines R₂GeNR′ has been observed in the reaction of germylenes with phenyl azide (precursor of phenylnitrene). These transient derivatives lead, by polycondensation reactions, to the corresponding cyclic or linear germazanes

, and are characterized by insertion reactions into the germanium—nitrogen bond, cleavage and addition reaction with tetrahydrofuran, and pseudo-Wittig reactions with benzaldehyde. The latter produces the corresponding germoxanes via new

intermediates and phenyl benzaldimine.     

The third-order dynamic electric susceptibility of the hydrogen molecule

The dynamic third-order electric susceptibility of the hydrogen molecule has been computed. The results were obtained using the random-phase approximation, and for the parallel component give

= 702 au. This compares well with the experimental value of

= 777 ± 10 au.     

Etude calorimetrique et analytique de l'adsorption du cyanogene sur la silice

The adsoprtion of C₂N₂ on well outgassed specimens of SiO₂ at temperatures from 35 to 913°C has been studied by heat flow calorimetry, volumetry, and mass spectrometry.Small amounts of cyanogen are adsorbed at low temperature: reversibly by hydrogen bonding with the silanol groups, and irreversibly on strained siloxane bridges or Lewis acid sites. Above 200°C cyanogen reacts, with silanol groups, leading to the formation of HCN (partly reversibly adsorbed on non-reacted silanol groups) and silyl isocyanate:

. The process is complete at 418°C and the measured enthalpy for the reaction

is ΔH = ?12.2 ± 0.3 kcal mole^?.Above 500°C, HCN and C₂N₂ react with ordinary siloxane bridges. At higher temperature, the pyrolysis of

produces CO₂ with CO and N₂ (in smaller quantities), showing that a large proportion of N-atoms are bonded on the surface.     

η2-acylcarbonylvanadium-verbindungen

Substituted vanadium carbonyl compounds with η²-bonded acyl ligands (η²-RCO)V(CO)₃

(

= ditertiary phosphines or arsines: dppe, dppp, dppm, diars, arphos, dpase) have been prepared by photochemical reaction of [V(CO)₄

] with various substituted benzoyl chlorides and cyclopropanylcarbonyl chloride.Effects of aromatic substituents and

upon the thermal stability of the η²-acylcarbonylvanadium compounds are discussed. IR ν(CO) force constants and ⁵¹V NMR signals are linearly correlated with Hammett's σ constants of the aromatic substituents.The preparation of V(CO)₂Cl(diars)₂ is described.     

Vibronic interaction between nπ and ππ states and phosphorescence of Norharmane

Solvent effects on phosphorescence and excitation spectra and its polarization characteristics indicate that the two major spin-orbit coupling mechanisms through which the ³ππ^* state of Norharmane acquires dipole-allowed character via nπ^* states are: