(Aroxymethyl)trifluoro- and methyl(aroxymethyl)fluorosilanes

Conclusions (Aroxymethyl)trifluorosilanes and methyl(aroxymethyl)fluorosilanes with the general formula XC₆H₄OCH₂SiM_nF₃-n (n=0, 1) were synthesized and their reactivity with electrophilic reagents was studied.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2148–2150, September, 1985.     

Solvatochromism of Heteroaromatic Compounds: XIII. Methyl(aroyloxymethyl)fluorosilanes and (Aroyloxymethyl)trifluorosilanes

The UV spectra of heptane solutions of methyl(aroyloxymethyl)fluorosilanes and (aroyloxymethyl)trifluorosilanes of the general formula 4-RC₆H₄COOCH₂Si(Me)_{3 - 4n} F _n (n = 1-3; R = H, F, Cl, Me, MeO, O2N) were studied. The intramolecular coordination bond Oarr;Si causes a bathochromic shift of the second -* transition, because the energy gap between the ground electronic and Franck-Condon excited states decreases owing to additional stabilization of the latter. The spectral shifts correspond to stabilization of the five-coordinate state of the silicon atom in (aroyloxymethyl)trifluorosilanes by 5-6 kcal mol^{- 1}.     

Ruthenium(IV) and Osmium(II) Tetraphenylporphine Complexes: Synthesis and Oxidation Reactions

The Ru(IV) and Os(II) complexes (PhO)₂RuTPP and OsTPP were synthesized from tetraphenylporphine (H₂TPP) and K₂RuO₄ or K₂OsO₄ (taken in the molar ratio of 1 : 30) in boiling phenol. The kinetics of oxidation reactions of these complexes in solutions of HOAc (acetic), H₂SO₄, and HOAc–H₂SO₄ acids was studied. It was found that in the aerated HOAc–H₂SO₄ mixture heated above 340 K, these complexes are oxidized with participation of different reaction sites: the Ru(IV) complex is oxidized at macrocycle to give the -radical-cation (PhO)₂RuPP⁺, while in the Os(II) complex, the metal atom is oxidized to form the Os(III) complex. In the first case, the reaction follows the activation mechanism, whereas in the second case, the activation energy of the reaction is zero.     

Iodomethyl phenyl sulfoxide: reactivity and synthetic applications

Lithio iodomethyl phenyl sulfoxides reacted with alkyl halides and carbonyl compounds to give adducts in good to moderate yields. Solvolysis of the carbonyl adducts led to sulfones or the ring expanded product.     

Hydrolysis of fluorosilanes: a theoretical study

Hydrolysis and condensation of simple trifluorosilanes, HSiF3 and MeSiF3, was studied by quantum mechanical methods. Hydrolysis of fluorosilanes is highly endothermic. The Gibbs free energy of the first reaction step in the gas phase is 31.4 kJ/mol, which corresponds to an equilibrium constant of 10(-6). Hydrolysis of the subsequent fluorine atoms in trifluorosilanes is thermodynamically more unfavorable than the first step of substitution. No significant difference in thermodynamics of hydrolysis was found between HSiF3 and MeSiF3. The activation energy for hydrolysis by a water dimer is significantly lower than that for hydrolysis by a water monomer. The former reaction is also less unfavorable thermodynamically, due to a high binding energy of the HF-H2O complex formed as a product of hydrolysis. Self-consistent reaction field (SCRF) calculations show that hydrolysis of trifluorosilanes in aqueous medium has lower activation energy than in the gas phase. It is also thermodynamically less unfavorable, due to better solvation of the products. Homofunctional condensation of HSiF2OH is thermodynamically favored. The equilibrium mixture for hydrolysis/condensation of RSiF3 in water is predicted to contain ca. 2.3% disiloxane (HF2Si)2O, if 100-fold excess of water relative to silane is assumed. Further hydrolysis of (HF2Si)2O is negligible. The thermodynamics of fluorosilane hydrolysis contrasts with that of chlorosilanes, where both hydrolysis and condensation are strongly favorable. Moreover, in the case of trichlorosilanes each subsequent hydrolysis step is more facile, leading to the product of full hydrolysis, RSi(OH)3.     

Pyridine Oximes: Synthesis, Reactions, and Biological Activity. (Review)

Data on methods for the production of pyridine aldoximes, ketoximes, amidoximes, and their derivatives and their reactions are reviewed. The synthesis of new heterocycles from pyridine oximes is discussed separately. The principal results of research into the biological activity of the oximes are presented.     

Pyrrole Oximes: Synthesis, Reactions, and Biological Activity. (Review)

Data on the production methods and reactions of pyrrole aldoximes and ketoximes and their derivatives are reviewed. The synthesis of new heterocycles from the pyrrole oximes is examined separately. The principal results from investigation of the biological activity of pyrrole oximes are described.     

Quinoline Oximes: Synthesis,Reactions, and Biological Activity. (Review)

Data on the production and the reactions of quinoline aldoximes and ketoximes and their derivatives are reviewed. The synthesis of new heterocycles based on quinoline oximes is examined separately. The main results from investigation of the biological activity of quinoline oximes are presented.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 163–190, February, 2005.     

Tris(2-methoxy-5-chlorophenyl)antimony: Synthesis and Oxidative Addition Reactions

Russian Journal of General Chemistry - The reaction of 2-methoxy-5-chlorophenyllithium with SbCl3 (3 : 1) in diethyl ether has afforded tris(2-methoxy-5-chlorophenyl)antimony, which has been...     

Synthesis and Reactions of 1,1-Dimethyl-3-oxobutyl-isothiocyanate (DMO-ITC)

In this review an attempt has been made to compile all the existing comprehensive literature for the synthesis of 1,1-Dimethyl-3-oxobutyl-isothiocyanate (DMO-ITC) and its reactions with the compounds having different functional groups, such as amines, diamines, amino alcohols, amino phenols, amino thiophenols, amino nitriles, amino acids, and hydrazines. The peculiar behavior of the DMO-ITC is due to its sensitivity toward acids and gives different products when the reaction occurs in the absence and presence of an acid. The pH of the reaction condition also plays an important role. Normally, DMO-ITC gives pyrimidinethione derivatives when treated with amines, but reactions become interesting when the compounds have an amino group as well as the other functional group (NH 2 , OH, SH, CN, COOH) at ortho position, providing condensed bicyclic, tricyclic, or poly heterocycles with ring nitrogen and/or sulfur is of biological importance. The reaction of DMO-ITC with ethylene diamine, o -phenylenediamines, 1,2-diaminoanthraquinone, o -diaminonaphthalenes, N -aminoethyladenosine, 2-amino ethanol, o -aminophenols, o -aminothiophenols, o -aminobenzonitriles, and o -aminobenzoic acids gave imidazopyrimidinethione, pyrimidobenzimidazolethiones, pyrimidoanthraquinonimidazolethione, pyrimidonaphthoimidazolethiones, furanopurinimidazopyrimidinethione, oxazolopyrimidinethione, oxafluorenethiones, thiafluorenethiones, thioxophenanthreneones, and thiaphenanthreneones derivatives respectively. But similar reactions were not seen with o -diaminoheterocycles. Hydrazines derivatives gave seven-membered heterocycles, that is, triazepinethiones derivatives. The synthesis of the heterocycles are well defined in separate sections according to the update references.     

Synthesis and Selected Reactions of 4(5)-Functionalized 2(3)-Furoyl Phosphonates

Russian Journal of General Chemistry - Approaches to the synthesis of a wide range of phosphorylated derivatives of 3-(furyl)acrylic acid and 4-(furyl)buten-2-one with various functional groups in...     

Furan and Thiophene Oximes: Synthesis, Reactions, and Biological Activity. (Review)

Data on methods for the production of furan and thiophene aldoximes, ketoximes, and amidoximes and their reactions are reviewed. The synthesis of new heterocycles from furan and thiophene oximes and the biological activity of derivatives of the oximes are discussed individually.     

N-Acyl-and N-Phosphorylpolyhalogenoalkyl-Imidolylphosphonates: Synthesis and Reactions

Abstract

Methods of synthesis of polyhalogenoalkylimidoyl phosphonates, the phosphorus analogs of a well-known and widely used acylimines of polyhalogenocarbonyl compounds, have been developed.     

Indole and Isatin Oximes: Synthesis, Reactions, and Biological Activity. (Review)

Data on methods for the production of isatin and indole aldoximes, ketoximes, and amidoximes and their reactions are reviewed. Individual syntheses of new heterocycles from indole and isatin oximes are discussed. The principal results from investigation of the biological activity of derivatives of the oximes are also presented.