The reaction of β-dicarbonyl compounds with trifluoromethylsulphenyl chloride. Part I. CF3S-substituted esters,anilides of β-keto acids,and their Schiff bases: Synthesis and stability.

The reactions of the β-keto acid derivatives with trifluoromethylsulphenyl chloride were carried out to give the α-SCF₃ substituted esters, anilides, and their Schiff bases of acetyl- and benzoylacetic acids. Ethyl esters of α-(trifluoromethylthio)acetoacetic and α-(trifluoromethylthio)benzoylacetic acids heated in dimethylsulphoxide/water solution give trifluoromethylthioacetone and ω-(trifluoromethylthio)acetophenone respectively, whereas with potassium hydroxide solution they form trifluoromethylthioacetic acid in a good yield.     

The reaction of β-dicarbonyl compounds with trifluoromethyl-sulphenyl chloride Part II. The synthesis of 3-SCF3 substituted 2- and 4-quinolinones

3-SCF₃ substituted 4-methyl-2(1H)-, 4-phenyl-2(1H)-, 2-methyl-4(1H), and 2-phenyl-4(1H)-quinolinones were obtained by cyclization of the respective -SCF₃ submitted acetoacetanilides or benzoylacetanilides or their β-phenylimino analogues in concentrated sulphuric acid upon heating. The structures of the compounds obtained were elucidated by elemental analysis and their IR, ¹H and ¹⁹F NMR, and mass spectra.     

Regioselective synthesis of linalyl compounds via addition reaction of geranyl bromide and tin with carbonyl compounds

Linalyl alkyl or aryl carbinols were regioselectively synthesized by the reaction ofgeranyl bromide and powdered tin with aldehydes and ketones.     

The band structures of some transition metals and their NaCl-type compounds

The band structures of Group IVB (Ti,Zr,Hf),VB (V,Nb,Ta) and VIB (Cr,Mo,W) transition metals and some of their carbides and nitrides (TiN,ZrN,HfN,VC,NbC,TaC,VN,NbN,TaN) with NaCl-type (Bl-type) structure have been calculated by using the tight-binding method within the Extended Hiickel approximation (EHT).The energy bands,densities of states and crystal orbital overlap populations are given.The relationship between the bonding properties and the superconducting transition temperatures (Tc) of them is discussed.The influences of various kinds of metallic atoms and changes of bond lengths on Tc are also discussed.     

The reaction of Tanshinones with Amines

The reaction of cryptotanshinone and tanshinone IIA with several biogenic amine metabolites involved in the pathogenic pathways of HE were investigated and eight 1,2,3,4-tetrahydrophenanthrene derivatives,2-6 and 8-10,were obtained.The probable mechanism on reaction was discussed.     

The reaction of carbohydrates and uronic acids with β-methylindole

Aldo- and ketu-hexoses produce with β-methylindole a pigment that is soluble with blue color in chloroform. The same applies to ω-hydroxymethylfurfural. Pentoses and uronic acids as well as furfural produce an olive color reaction, but no blue Soluble pigment. Methylpentoses and methylfurfural produce a red pigment, the chloroform extract of which is of raspberry color. The behavior of the heptoses is not characteristic. There is no possibility of differentiating between glucurone and galacturonic acid.     

α-Amination and the 5-exo-trig cyclization reaction of sulfur-containing Schiff bases with N-phenyltriazolinedione and their anti-lipid peroxidation activity

Triazolinedione quenches efficiently the 1,2-dipoles from Schiff bases of glycine esters which are formed via a [1,2-H]-prototropic shift of their α-hydrogens, and affords the respective α-aminated products in good yields. Competition experiments show a stabilization of the 1,2-dipole from the sulfide substituent. 5-exo-trig cyclization of N-PhTAD with Schiff bases of other amino acids gave triazolines. The antioxidative and lipoxygenase inhibitory activities of the novel synthesized compounds were studied.     

The reaction of α-stannylmethyllithium with esters

Ketonic compounds were prepared from esters using α-stannylmethyllithium as the reagent.     

α-Amino acetals containing a phosphonate or phosphine oxide group. Synthesis and reactions with resorcinols

New α-amino acetals containing a phosphonate or phosphine oxide group were synthesized by the Kabachnik-Fields reaction in the ternary system amino acetal-paraformaldehyde-dialkyl phosphonate (or dialkylphosphine oxide). Condensation of dialkyl (2,2-dimethoxyethylamino)methylphosphonates with resorcinol and its derivatives in ethanol in the presence of hydrochloric acid, apart from the corresponding 2,2-bis(polyhydroxyphenyl) ethylammonium salts, gave 2,5-bis(polyhydroxyphenyl)-1,4-bis[(dialkoxyphosphoryl)methyl]-piperazines. Dialkyl[(2,2-dimethoxyethylamino)methyl]phosphine oxides (Alk = C₈H₁₇, C₁₀H₂₁) did not react with resorcinol derivatives under similar conditions, and analogous ammonium salts were obtained by heating the reactants in boiling trifluoroacetic acid.     

Kinetics and mechanism of reaction of cis-α,β-dinitrostilbene with morpholine

Reaction of cis-,-dinitrostilbene (substrate) with morpholine (reagent) in n-hexane leads to cis--nitro--morpholinostilbene (end product). The process is of first order with respect to the substrate and second order with respect to the reagent. Possible reaction mechanisms are analyzed, and it is established that the following are most probable on the basis of kinetic patterns and stereochemistry: development of a charge transfer complex having a hydrogen bond between the substrate nitro group and reagent amino group; reaction of the complex with a second reagent molecule and formation of a carbanion (this stage determines the overall reaction rate); and detachment of a nitrite ion from the nitrocarbanion and its protonation to form the end product.N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 117977 Moscow. A. N. Nesmeyanov Institute of Heteroorganic Compound, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 78–83, January, 1992.     

Reaction of a chlorovinylcarbene with ketenealkyl silyl acetals. Synthesis of new α- and β-allenic carboxylates.

The reaction of ketenealkylsilylacetals with 1,1-dimethyl-2,2,3-trichlorocyclopropane in the presence of methyllithium leads to cyclopropane compounds, which, when treated with tetrabutylammonium fluoride give α- or β-allenic carboxylates.     

The reaction of perfluoroalkanesulfonyl halides Ⅶ. Preparation and reactions of trifluoromethanesulfonyl bromide

The reaction between sodium trifluoromethanesulfinate, which was prepared from trifluorome-thyl bromide, with bromine in aqueous solution resulted in the formation of trifluoromethanesulfonylbromide (CF_3SO_2Br). CF_3SO_2Br reacted with alkenes and alkyne to give the corresponding adductswith the loss of SO_2 in good yields, and with compounds containing active hydrogen to give brominatedderivatives. A radical reaction mechanism was proposed and confirmed by EPR study.     

The reaction of N-phenyldialkynylimines with η5-cyclopentadienyldicarbonylcobalt

N-Substituted dialkynylimines react with η⁵-cyclopentadienyldicarbonylcobalt to give a mixture of η⁴-cyclobutadiene cobalt complexes, the structures of which have been determined by X-ray crystallography.     

Aliphatic acid dihydrazide derivatives of dicyclopentadienylzirconium(IV) dichloride and their reactions with β-diketones. Formation of cyclic compounds

The reactions of dicyclopentadienylzirconium(IV) dichloride with bidentate aliphatic acid dihydrazide (LH₂) derived from oxalic, succinic, and adipic acids (metal to ligand molar ratios 1 : 1 and 1 : 2, respectively) in anhydrous tetrahydrofuran in the presence of base led to the formation of the [Cp₂Zr(L)] and [CpZr(LH)₂Cl] complexes. The complexes were characterized by elemental analyses, electrical conductance, magnetic measurements and spectroscopic studies. These ligands appear to behave as bidentate chelate agents. All the complexes contain terminal amino or terminal hydrazinc nitrogen atoms with an unshared electron pair, enabling nucleophilic condensations. Therefore, the reactions of these complexes with β-diketones (acetylacetone, benzoylacetone, dibenzoylmethane, thenoyltrifluoroacetone) in the presence of glacial acetic acid have been studied viz., ring closure and formation of macrocyclic ligand (mac) complexes. Two types of cyclic products viz., [Cp₂Zr(mac)] and [CpZr(Mac)Cl] were isolated. The spectral studies of these cyclic products are reported.     

Studies on the reaction of α-imino esters with organometallic compounds

Benzylzinc reagent reacted with α-imino ester (2) at the α-carbon exclusively, though other organometallic reagents such as Mg. Al, Cu, Tl, and B derivatives reacted at the nitrogen atom. Use of the (S)-amine as a chiral auxiliary of 2 created the R chirality at the imino carbon. Very high chiral Induction was realized In the reaction of prenylzinc reagent wlih α-imino 8-(-)phenylmenthyl ester (10). The reaction of 2 with heteroatom substituted allylic organometalic compounds (15) gave the corresponding α-heterostom substituted amino acid derivatives (16). Here again, the allylic zinc reagent gave the adduct in higher yield than the corresponding Tl, Al, and B reagents.     

The reaction of α-chloro-α-phenylthioketones with phenols: An alternative synthesis of benzofurans

A new synthesis of benzofurans has been developed using the Lewis acid catalysed reaction of readily available α-chloro-α-phenylthioketones with phenols.