Synthesis and photophysical properties of soluble polyimides and polyquinazolones containing side-chain chalcones or azo chromophores

Soluble aromatic and carboxyl- and hydroxyl-containing polyimides, mixed polyimides, and polyquinazolones of various chemical structures, as well as a series of new dicyanoazobenzene chromophores, are synthesized. From 20 to 80 mol % of chromophore groups are incorporated into side chains of the polymers. The thermal, photosensitive, and nonlinear optical properties (second-harmonic generation) of the chromophore-containing polymers are investigated. The polymers with covalently attached groups of the dye DR-13 or azo-derivatives of 4-phthalonitrile demonstrate the highest nonlinearity. The T _g values of the polyimides vary from 165 to 215°C; their temperatures corresponding to 5% weight loss lie in the range 290–350°C; and the measured coefficients of second-harmonic generation, d ₃₃, for a number of polarized films based on chromophore-containing polymers attain several tens of picometers per volt. The incorporation of chromophore groups into the side chains of the polymers causes an increase in the photosensitivity of polyimides by an order of magnitude relative to that of the parent polymers (S _0.1 = (3?4) × 10⁵ cm²/J in the range of dye absorption).     

Products of the reaction of 2-chloro-6-thio-7-methyl-purine with amines

Treatment of 2-chloro-6-thio-7-methylpurine with aniline, piperidine, or morpholine with heating in DMF gives 2-phenylamino(piperidino or morpholino)-6-thio-7-methylpurine. The scheme for the formation of the side products 2,6-dithio-and 2,6-dipiperidino-7-methylpurine is discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 82–84, January, 2000.     

Synthesis and some properties of 6-(ω-aroylbutylthio)purines

A series of 6-(ω-aroylthio)purines, which have not been described in the literature, has been obtained by the reaction of 6-purinethione with ω-chlorovalerophenone and its substituted derivatives. Some properties of the compounds synthesized have been studied, viz. reaction at the carbonyl group, methylation, and hydrolysis. All-Russian Scientific Center for the Safety of Biologically Active Substances, Staraya Kupavna, Moscow region 142450. Zaporozhe State Medical University, Zaporozhe 330074, Ukraine. Center for Drug Chemistry, All-Russian Pharmaceutical Chemistry Research Institute, Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1407–1411, October, 1999.     

Synthesis of n2-alkyl(aryl,dialkyl, cycloalkyl)guanines

Novel N²-alkyl(aryl, dialkyl, cycloalkyl)guanines have been synthesized by treating 2-chloro-7-benzylhypozanthine with amines and debenzylation of the N²-substituted 7-benzylguanine products by means of palladium catalyzed hydrogenation.DeceasedCenter for the Chemistry of Medicinal Compounds. All Russian Chemico-Pharmaceutical Science Research Institute, Moscow, 119815. State Institute for Blood Substitutes and Medicinal Preparations, Moscow, 109044. Zaporozh'e State Medicinal Institute, Zaporozhe'e, 330074. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 391–394, March, 1996. Original article submitted January 6, 1996.     

Preparation and reactivity of metal-containing monomers

Thermal transformations (at 340 to 390 °C) of coprecipitates of iron and cobalt acrylates, [Fe₃O(CH₂CHCOO)₆OH][Co(CH₂CHCOO)₂]_2.4 (1) and [Fe₃O(CH₂CHCOO)₆OH][Co(CH₂CHCOO)₂]_1.5·3H₂O (2), are studied. The dependence of the degree of gas evolution () on time is described by the equation () wherek ₁=2.3 · 10¹² · exp[–49500/(RT)] s^–1,k ₂=6.0 · 10⁶ · exp[–33000/(RT)] s^–1 andk ₁=2.6 · 10¹² · exp[–49000/(RT)] s^–1,k ₂=6.6 · 10⁵ · exp[–30000/(RT)] s^–1 for cocrystallizates1 and2, respectively. The coefficient ₁ decreases as the temperature increases. The value of ₁ for compound1 is higher than that for compound2. The composition of products of the transformations of1 and2 are studied. The main solid state products of the decomposition are nanometer-sized particles of cobalt ferrite, CoFe₂O₄, with a narrow size distribution stabilized by the polymeric matrix. The thermal transformations of cocrystallizates1 and2 include dehydration, thermal decomposition, copolymerization in the solid state, and decarboxylation of the metallocarboxylate groups of the polymer. The effect of the ratio between the Fe clusters and the Co-containing fragments on the process of thermal transformation is analyzed.For Part 40, seeRuss. Chem. Bull., 1994,43, 2020.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 885–893, May, 1995.The authors are grateful to A. N. Titkov for optical microscopic and electron microscopic studies.     

Synthesis and molecular structure of platinum(II) complexes with cyclotriphosphazenes containing pyridylalkylamino and pyridylmethoxy groups

The interaction of platinum(II) nitrile complexes with polydentate ligands, pentaphenoxy(2-pyridylmethylamino)cyclotriphosphazene (L¹), pentaphenoxy(3-pyridylmethylamino)cyclotriphosphazene (L²), pentaphenoxy[2-(2-pyridyl)ethylamino]cyclotriphosphazene (L³), and pentaphenoxy(2-pyridylmethoxy)-cyclotriphosphazene (L⁴), was studied. The synthesized complexes were characterized by single-crystal X-ray diffraction, ¹H and ³¹P NMR spectroscopy, IR spectroscopy, FAB mass spectrometry, and other methods. In complexation of phosphazenes L¹-L³ with Pt(II) ions, nitrogen atoms of the pyridine ring and alkylamine fragment participate in the coordination to form chelate rings. In the complex with L⁴, the substituted phosphazene is coordinated via nitrogen atoms of the pyridyl group and cyclotriphosphazene ring to form a sevenmembered ring.     

Synthesis of N6-substituted adenines from 3-methylxanthine

A series of 6-arylalkyl(hetarylalkyl, cycloalkyl, carboxyalkyl)amino-7-benzyl-2-chloropurines have been synthesized from 3-methylxanthine via the reaction of the intermediate 7-benzyl-2,6-dichloropurine with amines and aminoacids. N⁶-benzyladenine, N⁶-(-furfuryl)adenine (kinetin), and N-(purinyl)glycine have been obtained via the catalytic hydrogenation of 7-benzyl-6-benzyl(furfuryl, carboxymethyl)amino-2-chloropurines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, 529–532, April, 2000.