2-benzazepines. 10 [1]. New d-fused 2-benzazepines

Pyrano[3,2-d][2]benzazepines were synthesized by reaction of the beta-dimethylamino unsaturated ketone 1 with malonic ester or the anion of t-butyl acetate. Conversion of the pyrano derivative to the pyrido[3,2-d]-[2]benzazepine was achieved in low yield. A pyrrolo[3,2-d][2]benzazepine was prepared via an oxazepino-[6,7-d][2]benzazepine which was obtained by reaction of 1 with the anion of ethyl isocyanoacetate.     

10-Alkenylphenothiazines. 2. Synthesis and mechanism of acidic hydrolysis of cis- and trans-10-2-phenylvinyl)phenothiazines

The addition of phenothiazine to phenylacetylene in super-base media proceeds regio- and stereoselectively and leads to the predominant formation of cis-10-(2-phenylvinyl)phenothiazine, which is completely converted to its trans-isomer at 200C. Kinetic analysis of the acidic hydrolysis of the cis- and transisomers has allowed us to assign to it an AS_E2 reaction mechanism, similar to the mechanism of hydrolysis of vinyl alkyl ethers.For Communication No. 1, see [1].Translated from Khimiya Geterotsicheskikh Soedinenii, No. 10, pp. 1420–1424, October, 1986.     

Novel Copolymers of Styrene. 10. Halo Ring-Substituted 2-Cyano-3-phenyl-2-propenamides

Novel electrophilic trisubstituted ethylene monomers, halo ring-substituted 2-cyano-3-phenyl-2-propenamides, RPhCH ? C(CN)CONH₂, where R is 2-bromo, 3-bromo, 2-fluoro, 3-fluoro, 2-iodo, 3-iodo, and 4-iodo were prepared and copolymerized with styrene. The monomers were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and cyanoacetamide, and characterized by CHN elemental analysis, IR, ¹H- and ¹³C-NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator, ABCN at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, ¹H- and ¹³C-NMR, GPC, DSC, and TGA. High T_g of the copolymers in comparison with that of polystyrene indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (7-19 wt%), which then decomposed in the 500–800°C range.     

Characterisation of porous silica. 2. CPG-10 (VYCOR)

Porous silica CPG-10 has been characterised by adsorption of benzene before and after modification with trimethylchlorosilane. The Brunauer–Emmet–Teller (BET) specific surface areas were determined where possible. Modification of CPG-10 reduces its adsorption for benzene and hence reduces the BET specific surface area, with the extent of reduction depending on the extent of modification. For a fully modified sample with the highest surface concentration of trimethylsilyl groups, the adsorption isotherm changes from type IV of the unmodified sample to type V. The hysteresis loop size and position are also altered. A mechanism for multilayer adsorption and capillary condensation in modified porous silica is proposed.     

Novel copolymers of styrene. 10. halogen ring-disubstituted butyl 2-cyano-3-phenyl-2-propenoates

Novel trisubstituted ethylenes, halogen ring-disubstituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH?C(CN)CO₂C₄H₉ (where R is 2,5-diBr, 3,5-diBr, 2,3-diCl, 2,4-diCl, 2,5-diCl, 2,6-diCl, 3,4-diCl, 3,5-diCl) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-disubstituted benzaldehydes and butyl cyanoacetate, and characterized by CHN analysis, IR, ¹H and ¹³C-NMR. All the ethylenes were copolymerized with styrene (M₁) in solution with radical initiation (ABCN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, ¹H and ¹³C-NMR. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200–500°C range with residue (2–5% wt.), which then decomposed in the 500–800°C range.     

Unexpectedly facile isomerisation of [7,10-Ph2-7,10-nido-C2B10H10]2- to [7,9-Ph2-7,9-nido-C2B10H10]2-

The 2e-reduction of 1,12-Ph2-1,12-closo-C(2)B(10)H(10) followed by oxidation or metallation gives products that arise from [7,9-Ph2-7,9-nido-C(2)B(10)H(10)](2-), formed by unexpectedly facile isomerisation of the kinetic 7,10-isomer: the 4,1,6-MC(2)B(10) compounds which result are progressively isomerised to 4,1,8- and 4,1,12-isomers for M = {CpCo} but to an equilibrium mixture of 4,1,8- and 4,1,12-isomers for M = {(arene)Ru}.     

Synthesis of halogenated polyhedral phosphaboranes. Crystal structure of closo-1,7-P2B10Cl10

The 12-vertex closo-phosphaborane 1,7-P2B10Cl10 (1) has been prepared in low yield from the pyrolysis reaction of B2Cl4 with PCl3 at temperatures above 400 degrees C. A single-crystal X-ray structure determination of 1 (monoclinic space group P2(1)/n with a = 9.239(2) A, b = 16.786(3) A, c = 15.739(3) a, beta = 93.25(3) degrees, and Z = 4) confirmed that, consistent with its 26 skeletal electron count, the phosphaborane adopts a distorted icosahedral structure with the phosphorus atoms in the 1,7-positions. Crystals of 1 contain toluene in a 1:1 molar ratio embedded between each P atom of neighboring cluster molecules. Alteration of the pyrolytic conditions resulted in the formation of the phosphaboranes P4B8Cl6 (2) and P2B8Cl8 (3), which were characterized spectroscopically. Copyrolysis of B2Cl4 with a mixture of PCl3 and AsCl3 at 450 degrees C generated the six-vertex arsaphosphaborane AsPB4Cl4 (4) and traces of the icosahedral arsaphosphaborane AsPB10Cl10. These compounds are examples of heteroboranes which contain two different group-15 atoms within a single molecule.     

Synthetic Studies on Coenzyme Q10. Part 2

An improved route to coenzyme Q₁₀ ( 1 ) starting from commercially available coenzyme Q₁ is described. The key steps in this synthesis are the SeO₂‐mediated oxidation of the protected isoprenylhydroquinone 3 into the (E)‐allyl alcohol 5 without the formation of undesired stereoisomer and the one‐pot reductive elimination of the phenylsulfonyl and dibenzyl groups in 7 by using naphthalenyllithium.     

Novel copolymers of styrene. 10. Bromo and chloro ring-disubstituted propyl 2-cyano-3-phenyl-2-propenoates

Novel trisubstituted ethylenes, ring-disubstituted propyl 2-cyano-3-phenyl-2-propenoates, RPhCH = C(CN)CO₂C₃H₇ (where R is 2-bromo-4-methyl, 2-chloro-6-methyl, 3-chloro-4-methyl, 2,5-dibromo, 3,5-dibromo, 2,3-dichloro, and 2,4-dichloro) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and propyl cyanoacetate and characterized by CHN elemental analysis, IR, ¹H and ¹³C-NMR. All the ethylenes were copolymerized with styrene in solution with radical initiation (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, ¹H and ¹³C-NMR, GPC, DSC, and TGA. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500°C range with residue (7-12% wt.), which then decomposed in the 500-800°C range.     

Nonplanar aromatic compounds. 5. A atrategy for the synthesis of cis-10b,10c-dimethyl-10b,10c-dihydropyrenes. First crystal structure of a cis-10b,10c-dimethyl-10b,10c-dihydropyrene.

Through the use of a potentially removable tether, a heavily substituted 10b,10c-dimethyl-10b,10c-dihydropyrene (DMDHP), 20, was synthesized exclusively as the cis-isomer. It exists as the major component (20:1) in an equilibrium with its valence isomer syn-[2.2]metacyclophanediene 19. An X-ray crystal structure determination of 20, a cis-(2,7)-10b,10c-dihydropyrenophane, provided the first experimental measurements of the cis-DMDHP skeleton. The observed bond alternation in the [14]annulene was found to be larger than that of the corresponding trans-DMDHP framework. Prior MMPI calculations, on which previous discussion of the structure of the cis-DMDHP system had been based, are in very good agreement with the experimental results. Our own DFT calculations predict a more symmetric and more bond equalized structure than was observed in 20.     

Novel Copolymers of 4-Fluorostyrene. 10. Some Ring-substituted 2-Phenyl-1,1-dicyanoethylenes

Novel copolymers of trisubstituted ethylene monomers, ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC₆H₂CH=C(CN)₂ (where R is 4-C₆H₅O, 2-C₆H₅CH₂O, 3,4-(C₆H₅CH₂O)₂, 2-C₆H₅CH₂O-3-CH₃O, 3-C₆H₅CH₂O-4-CH₃O, 2-Cl-6-NO₂, 4-Cl-3-NO₂, 5-Cl-2-NO₂) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, ¹H and ¹³C-NMR. The order of relative reactivity (1/r ₁) for the monomers is 3,4-(C₆H₅CH₂O)₂(31.0) > 2-C₆H₅CH₂O-3-CH₃O (24.8) > 3-C₆H₅CH₂O-4-CH₃O (15.2) > 4-C₆H₅O (3.1) > 4-Cl-3-NO₂ (1.9) > 2-Cl-6-NO₂ (1.6) > 5-Cl-2-NO₂ (1.5) > 2-C₆H₅CH₂O (1.4). High T_g of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in the 270-400°C range with residue, which then decomposition in 400–800°C range.     

ChemInform Abstract: Nickel Vanadium Tellurium Oxide,NiV2Te2O10.

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