I. A. Tokareva

Alkylation of 1,2,3-benzotriazole with iodomethyl ketones

Solvent-free reactions of 1,2,3-benzotriazole with 1-iodopropan-2-one and 1,3-diiodopropan-2-one in the absence of a catalyst involved alkylation of the heteroring at the N1 atom and subsequent quaternization at the N3 atom with formation of 1,3-bis(2-oxopropyl)-1H-1,2,3-benzotriazolium triiodide which is a new conducting ionic liquid. The reaction of 1,2,3-benzotriazole with 1,3-diiodopropan-2-one was accompanied by reductive deiodination of the iodomethyl groups in the initial ketone with hydrogen iodide liberated by N1-alkylation. Triiodide ion readily exchanges for nitrate ion by the action of AgNO3 to produce 1,3-bis(2-oxopropyl)-1H-1,2,3-benzotriazolium nitrate. The reaction of 1,2,3-benzotriazole with 2-iodo-1-phenylethan-1-one in melt resulted in the formation of 1,3-bis(2-oxo-2-phenylethyl)-1H-1,2,3-benzotriazolium triiodide.

New synthesis of poly(phenothiazine-3,7-diyl)

Development of the chemistry of phenothiazine is stimulated by therapeutic effect of some its derivatives in the treatment of nervous system disorders [1]. At present, researchers’ interest is focused on the synthesis and properties of macromolecular systems based on phenothiazine. It is known that polyphenothiazine derivatives exhibit unique electrical and photoelectric properties [2]. Poly(phenothiazine-3,7-diyl) compounds are commonly prepared by the Grignard and Heck reactions in the presence of nickel and palladium catalysts [3, 4]. Unsubstituted poly(phenothiazine-3,7-diyl) was synthesized by phase-transfer oxidative polymerization using ammonium peroxosulfate as oxidant [5]. We were the first to reveal that photolysis of fused (130°C) 2-iodo-1-(10H-phenothiazin-10-yl)ethanone (I) in the absence of a catalyst yields 66% of iodinedoped poly(phenothiazine-3,7-diyl) (II). The reaction involves cleavage of the N–C, C–C, and C–I bonds and is accompanied by liberation of carbon(II) oxide and ethylene. The IR spectrum of the gas mixture contained absorption bands at 1640 and 3100 cm typical of stretching vibrations of the C=C and C–H bonds in ethylene molecule and a band at 2100 cm belonging to carbon(II) oxide. Presumably, migration of the radical center in the initially formed nitrogencentered phenothiazine radical to the 3(7)-position is followed by combination with formation of dimeric structures, which promotes 1,5-prototropic shifts. Further growth of the polymer chain is favored by abstraction of hydrogen atoms from C (C) by iodine radical.

Synthesis of poly(2,2′,3,3′-indole)

New approaches to the synthesis of poly(2,2′,3,3′-indole) were developed based on the photochemical dehydropolycondensation of indole in the presence of iodine and the photochemical polycondensation of 1-(1H-indol-3-yl)-2-iodo-1-ethanone in the absence of catalyst and solvent. A suggested mechanism for the formation of the oligomeric chain in these reactions includes the intermediate formation of 3,3′-diindole with subsequent polycondensation via elimination of hydrogen atoms at position 2 of the dimer pyrrole fragment.

Reaction of 1,3-dihalopropan-2-ones with 2-sulfanylbenzoic acid mono- and disodium salts

Well known biological activity of benzoic acid derivatives [1] prompted us to examine the possibility for building up novel heterocyclic systems by reactions of 2-sulfanylbenzoic acid monoand disodium salts with α,α′-dihalo ketones of the general formula XCH2C(=O)CH2X (Ia–Ic, X = Cl, Br, I). Initial sodium 2-sulfanylbenzoate (II) was prepared in situ according to the procedure described in [2] and was brought into reaction with 1,3-dichloropropan-2-one (Ia) in aqueous acetone at room temperature. The reaction occurred as intermolecular O-alkylation of sodium 2-sulfanylbenzoate (II) (Williamson reaction [3]) and led to the formation of 76% of previously unknown 2-oxo-3-(2-sulfanylbenzoyloxy)propyl 2-sulfanylbenzoate (III) (Scheme 1). The structure of compound III was confirmed by its elemental composition and IR and NMR spectra. The IR spectrum of III contained absorption bands belonging to stretching vibrations of S–H (2567 cm), ester carbonyl (1690 cm), and ketone carbonyl groups (1723 cm). Two methylene units in molecule III gave rise to signals at δ 5.38 ppm in the H NMR spectrum and at δC 67.58 ppm in the C NMR spectrum. In order to construct a heterocyclic system, bisbenzoate III was treated with 1,3-dihalopropan-2-ones Ia–Ic with a view to obtain S-alkylation products. However, these reactions resulted in the formation of sulfur-containing oligomers which were insoluble in organic solvents. We succeeded in synthesizing the desired monomeric cyclization product, compound V, only by reaction of disodium salt IV with dihalo ketones Ia–Ic (Scheme 2). Macrocyclic 5H,7H,11H,17Hdibenzo[g,n][1,5,9,13]dioxadithiacyclohexadecine5,8,11,18(9H,19H)-tetraone (V) was formed in 63%

Photoinitiated polymerization of 1-(iodomethyl)benzene in the absence of catalyst and solvent

Linear polybenzyl oligomers and polymers are analogs of parapolyphenylenes, which are widely used as materials for displays production, in electrophotography, at production of lighting sources, photodetectors, sensors, fi eld-effect transistors, laser diodes, thermo resistant polymer materials [1, 2].

Reactions of 1,3-dihalopropan-2-ones with sodium quinoline-8-thiolate

Mechanochemical reaction of sodium quinoline-8-thiolate with 1,3-dichloropropan-2-one gave 1-chloro-3-(quinolin-8-ylsulfanyl)propan-2-one. 1,3-Bis(quinolin-8-ylsulfanyl)propan-2-one was formed in the reaction of the same reagents in methanol solution. Mechanically activated reaction of sodium quinoline-8-thiolate with 1,3-diiodopropan-2-one resulted in the formation of 9,20-dioxo-8,9,10,19,20,21-hexahydro-[1,11,4,8]dithiadiazacyclotetradecino[2,3,4-ij: 10,9,8-i′j′]diquinoline-18,22-diium diiodide.

New photochemical transformations of 1-iodopropan-2-one

Photolysis of 1-iodopropan-2-one (λ = 254 nm) at 80–90°C in the absence of CCl4 was studied. The structure of obtained polymer was studied by 1H NMR, IR, and ESR spectroscopy.

Homopolycondensation of 1,3-dibromopropane-2-thione

Earlier we have found a high propensity of 1-bromopropane-2-thione to homopolycondensation at 20°С with the formation of linear soluble in organic solvents polymers of molecular mass 1400 [1]. The solutions of these polymers form black glittering coatings showing high adhesion to different supports (quartz, glass, aluminum), paramagnetism, electroconductivity (σ = 6.5×10 Sm cm) and photoconductivity (λmax = 450 nm).