Reaction of 2-acetyl-3-methoxy-5-methyldiazaphospholine with p-toluenesulfonyl azide

Conclusions Tosyl azide reacts with 2-acetyl-3-methoxy-5-methyldiazaphospholine to give an iminodiazaphospholine that is stable as a solid, while in solutions, depending on the nature of the solvent and the temperature, it changes to the tautomer with an NH bond and the dimer. The equilibrium interconversion of these three forms was shown on the basis of the IR and³¹P NMR spectra.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2635–2638, November, 1981.     

Reaction of 2-methoxy-3H-azepine with NBS: efficient synthesis of 2-substituted 2H-azepines

[reaction: see text] The reaction of 2-methoxy-3H-azepines, in the presence or absence of a nucleophile, with N-bromosuccinimide (NBS) gave a regioselective 1,4-adduct from which the corresponding 2H-azepine derivatives were formed via base-promoted hydrogen bromide elimination, generally in moderate to quantitative yield. Competitive formation of 4-bromo-2-methoxy-3H-azepine by electrophilic substitutuion or 3H-azepin-2-yl 2H-azepin-2-yl ether by transetherification was minimized at lower reaction temperatures. Quantitative substitution of 2-(2',4',6'-trichlorophenoxy)-2H-azepine derivatives, formed in moderate yield from the respective 3H-azepine and NBS in the presence of 2,4,6-trichlorophenol (TCP), by various nucleophiles gave the corresponding 2-substituted 2H-azepine. Among these nucleophiles were alkanethiol and alkylamine that are not tolerated in the reaction of 3H-azepine and NBS.     

硫代磷酰二氯与邻苯二酚反应

苯基硫代膦酰二氯与邻苯二酚在三乙胺存在下生成螺环五配位磷化物3.烷氧基, 烷胺基,烷硫基,烷基,苄基硫代磷酰二氯与邻苯二酚反应得到六配位磷化物8.讨论了这些反应的机理.     

Reaction of selenium dichloride with trimethylpropargylsilane

Russian Chemical Bulletin -     

Reaction of diselenium dichloride with acetylene

Russian Journal of Organic Chemistry -     

Reaction of 3-methoxy-17-methylmorphinan-6-one with formaldehyde

Reaction of 3-methoxy-17-methylmorphinan-6-one ( 1 ) and formaldehyde with the presence of calcium hydroxide in aqueous dioxane gave 7,7-bis(hydroxymethyl)-3-methoxy-17-methyl-5-methylenemorphinan-6β-ol ( 2a ). Catalytic reduction of 2a yielded the 5α-methyl compound, 2b . Tosylation of 2a,b followed by lithium triethylborohydride reduction gave either 7α-methyl-6β,7β-oxetanes 4a,b or 7,7-dimethyl-6β-ols 5a,b , depending on reaction conditions. The C-6 ketones 6a,b were prepared by oxidation of 5a,b . One compound in this series, 6a , had antinociceptive activity.     

Reaction of selenium dichloride with divinyl telluride

Russian Journal of Organic Chemistry -     

Temperature dependence of the mass accommodation coefficients of 2-nitrophenol, 2-methylphenol, 3-methylphenol, and 4-methylphenol on aqueous surfaces

The uptake of 2-nitrophenol, 2-methylphenol, 3-methylphenol, and 4-methylphenol on aqueous surfaces was investigated between 278 and 303 K, using the wetted-wall flow tube technique coupled with UV absorption spectroscopic detection. The uptake coefficients gamma were found to be independent of the aqueous phase composition and of the gas-liquid contact times. In addition, the uptake coefficients and the derived mass accommodation coefficients alpha show a negative temperature dependence in the temperature range studied. The mass accommodation coefficients decrease from 5.2 x 10(-3) to 8.3 x 10(-4), from 5.0 x 10(-3) to 3.1 x 10(-4), from 6.7 x 10(-3) to 7.3 x 10(-4), and from 1.2 x 10(-2) to 5.9 x 10(-4) for 2-nitrophenol, 2-methylphenol, 3-methylphenol, and 4-methylphenol, respectively. These results are used to discuss the incorporation of these species into the liquid using the nucleation theory. These data combined with the Henry's law constants were used to estimate the partitioning of the phenolic compounds between gaseous and aqueous phases and the corresponding atmospheric lifetimes under clear sky (tau(gas)) and cloudy conditions (tau(multiphase)) have then been derived.     

Reaction of vanadocene and vanadocene dichloride with ortho-iodobenzoic acid

At the interaction of bis (η⁵-cyclopentadienyl)vanadium with iodobenzoic acid or trimethylsilyl o-iodobenzoate in toluene depending on the ratio of the initial reagents bis(η⁵-cyclopentadienyl)vanadium(o-iodobenzoate) or η⁵-cyclopentadienylvanadium-bis-o-iodobenzoate were obtained in high yields. The latter was also formed in the reaction of bis(η⁵-cyclopentadiene)vanadium dihloride with trimethylsilyl o-iodobenzoate.     

Functionally substituted allenephosphonates and their transformation products 3. Reaction of phosphorus-containing 1-methoxy-2,3-alkadienes with 2-aminopyridines

A study was carried out on the reaction of aminopyridines with phosphorus-containing allenes. 2-Aminopyridines react to form phosphorylated pyrido-[1,2-a]-pyrimidines, while aminopyridines with monoalkylation at the exocyclic nitrogen atom form a mixture of 1,2- and 1,3-alkadienylphosphonates. A reaction mechanism was proposed.For previous communication see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 473–477, February, 1991.     

Reaction of sodium octahydrotriborate with biscyclopentadienylzirconium(IV) dichloride

Conclusions Sodium octahydrotriborate reacts with Cp₂ZrCl₂ in THF, ether or CH₂Cl₂ to give Cp₂ZrClBH₄.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 417–419, February, 1984.     

Thermodynamics of binding of 2-methoxy-3-isopropylpyrazine and 2-methoxy-3-isobutylpyrazine to the major urinary protein

In the present study we examine the thermodynamics of binding of two related pyrazine-derived ligands to the major urinary protein, MUP-I, using a combination of isothermal titration calorimetry (ITC), X-ray crystallography, and NMR backbone (15)N and methyl side-chain (2)H relaxation measurements. Global thermodynamics data derived from ITC indicate that binding is driven by favorable enthalpic contributions, rather than the classical entropy-driven hydrophobic effect. Unfavorable entropic contributions from the protein backbone and side-chain residues in the vicinity of the binding pocket are partially offset by favorable entropic contributions at adjacent positions, suggesting a "conformational relay" mechanism whereby increased rigidity of residues on ligand binding are accompanied by increased conformational freedom of side chains in adjacent positions. The principal driving force governing ligand affinity and specificity can be attributed to solvent-driven enthalpic effects from desolvation of the protein binding pocket.