Inna V. Tatarinova

A One-Pot Approach to Δ2-Isoxazolines from Ketones and Arylacetylenes

The sequential reaction of ketones with arylacetylenes and hydroxylamine in the presence of KOBu(t)/DMSO followed by the treatment of the reaction mixture with H(2)O and KOH leads to Δ(2)-isoxazolines in up to 88% yield.

Synthesis of Acyl Terphenyls and Higher Polyaromatics via Base-Promoted C–H Functionalization of Acetylarenes with Arylacetylenes

KO(t)Bu/DMSO-promoted C-H functionalization of acetylarenes with arylacetylenes (100 °C, 30 min), generating β,γ-ethylenic ketones, triggers upon further heating (100 °C, 4 h, with or without acidifying additive) the cascade assembly of acyl terphenyls and higher polyaromatics in good yields.

A One-Pot Synthesis of 2-Aminopyrimidines from Ketones, Arylacetylenes, and Guanidine

The three-component reaction of ketones, arylacetylenes, and guanidine catalyzed by the KOBut/DMSO system leads to 2-aminopyrimidines in up to 80% yield. Depending on structure of the starting ketones, the aromatization of intermediate dihydropyrimidines occurs either with loss of hydrogen molecules or methylbenzenes. The latter process takes place in the ketones, in which one of the substituents is not a methyl group. The reaction conditions are tolerable for dialkyl-, aryl(hetaryl) alkyl-, and cycloalkyl ketones.

C-vinylation of enolates with acetylenes in a one-pot synthesis of 4,5-dihydro-1 H -pyrazole-1-carbothioamides

β,γ-Unsaturated ketones are important building blocks in target-oriented syntheses of complex structures [2–4] and key intermediates in drug design [5–8]; therefore, addition of ketones to acetylenes opens new prospects in organic synthesis. Dienes A formed as intermediates in this reaction are equally or even more promising synthons. These intermediates can be subjected in situ to Oand C-alkylation and Diels– Alder reactions and converted into various heterocyclic compounds via addition of binucleophiles. In fact, we have recently synthesized 4,5-dihydroisoxazole derivatives by one-pot reaction from ketones, acetylenes, and hydroxylamine [9]. In order to extend the scope of the above synthetic approach, we have synthesized 4,5-dihydropyrazole1-carbothioamides 4a and 4b by one-pot three-component condensation of acetophenones 1a and 1b with phenylacetylene (2), and thiosemicarbazide (5) (Scheme 2). Presumably, the pyrazole ring is formed via addition of the NH2 group of thiosemicarbazide (5) to the carbonyl group of β,γ-unsaturated ketone 3 produced by hydrolysis of potassium enolate A (Scheme 3). The second reaction step is likely to be prototropic migration of the double bond to the α,β-position with respect to the hydrazone moiety. As a result, the nucleophilicity of the latter sharply increases, which facilitates pyrazole ring closure. Prototropic rearrangement should be favored by the presence of an equimolar ISSN 1070-4280, Russian Journal of Organic Chemistry, 2015, Vol. 51, No. 1, pp. 136–138.

Base-catalyzed addition of ketones to alkynes as a springboard to cycloalka[c]pyrazoline-2-carbaldehydes

Unknown cycloalka[c]pyrazoline-2-carbaldehydes are obtained in 52–68% yields when the intermediates of base-catalyzed addition of cyclic ketones to phenylacetylene are treated (without isolation) with hydrazine hydrate in formic acid.

Polymerization of N-vinylpyrroles: Recent achievements

The data on the polymerization of N-vinylpyrroles published for the most part during the past decade are systematized and summarized. Radical, cationic, and anionic polymerization of the mentioned monomers, which became easily accessible owing to the discovery and systematic development of their direct one-step synthesis from ketoximes and acetylene in the superbasic catalytic system KOH/DMSO (the Trofimov reaction), are discussed. Special attention is given to the physicochemical properties of the polymers (conductivity, paramagnetism, photosensitivity, and optical characteristics).

Free-radical cooligomerization of N -vinyl-4,5,6,7-tetrahydroindole with butyl vinyl ether

Oligo(N-vinyl-4,5,6,7-tetrahydroindole-co-butyl vinyl ethers) have been synthesized through free-radical cooligomerization with a yield of 84%. The copolymers are readily soluble in organic solvents (benzene, 1,4-dioxane, chloroform, and tetrahydrofuran), stable up to 380–400°C, and paramagnetic. (The concentration of paramagnetic centers is 1014 spin/g.) In addition, the copolymers exhibit the properties of organic semiconductors. (After being doped with iodine, σ = 1.1 × 10−7 S/cm.) The analysis of the 1H and 13C NMR spectra has shown that the oligomerization reaction is complicated by intramolecular cyclization involving carbon atoms located at the 2-position of pyrrole rings.

Copolymerization of N-vinylpyrrole-2-carbaldehydes with styrene, N-vinylpyrrolidone, and ethylene glycol vinyl glycidyl ether

Polyfunctional reactive copolymers of N-vinylpyrrole-2-carbaldehydes with styrene, N-vinylpyrrolidone, and ethylene glycol vinyl glycidyl ether are synthesized in the presence of AIBN (2 wt %, 80°C, 50 h) with a yield of up to 98% and a molecular mass of up to 4800. The copolymers show paramagnetic behavior (N = 2.0 × 1015−2.0 × 1017 g−1) and possess the properties of organic semiconductors (σ = 0.9 × 10−11–2.8 × 10−7 S/cm after doping with I2).

Nanoporous Crosslinked Macrocyclic Polyethers Based on Diethylene Glycol Divinyl Ether and Their Superbase Complexes with KOH

Nanoporous (11–12 nm) crosslinked macrocyclic polyethers with vinyloxy and hydroxyl groups have been synthesized by the free-radical polymerization of diethylene glycol divinyl ether (AIBN, 80°C, i-octane), followed by acidic hydrolysis. It has been shown that the polymers react with KOH to form insoluble superbase complexes and alcoholates capable of catalyzing vinylation of ethylene glycol by acetylene.

Three-Step Synthesis of 2-Acetyl-4-methyl-3,4-dihydropyran Oximes from Acetylbenzenes and Acetylene

Abstract2-Acetyl-4-methyl-3,4-dihydropyrans reacted with hydroxylamine in pyridine to give (E)-1-(4-methyl-3,4-dihydro-2H-pyran-2-yl)ethan-1-one oximes in up to 85% yield with high stereoselectivity.