Spirocyclohexadienones. 6. Three-component synthesis of 1-R-3,3-dimethyl-2-azaspiro[4.5]deca-1,6,9-trien-8-ones

1-R-3,3-Dimethyl-2-azaspiro[4.5]deca-1,6,9-trien-8-ones were synthesized through three-component condensation of anisole, isobutyraldehyde, and a corresponding nitrile in dichloromethane in the presence of concentrated sulfuric acid.     

Spirocyclohexadienones. 5. Synthesis of 2-R-7a-methyl-3-(spirocyclohexa-2,5-dien-4-one)perhydro-1-indolines

2-R-7a-Methyl-3-(spirocyclohexa-2,5-dien-4-one)perhydro-1-indolines were obtained by the reactions of 1-(4-ethoxyphenyl)-2-methylcyclohexanol with nitriles (RCN) in dichloromethane in the presence of concentrated sulfuric acid.     

Synthesis of 2-imidazolines by co-grinding of N-tosylaziridines and nitriles

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Spirocyclohexadienones. 4. Synthesis and dienone-phenolic rearrangement of 1-R-3,3-dialkyl-2-azaspiro[4.5]deca-1,6,9-trien-8-ones

The reactions of 1-(p-methoxyphenyl)-2-methylpropan-1-ol or -cyclohexyl-p-methoxybenzyl alcohol with nitriles RCN in concentrated sulfuric acid afforded 1-R-3,3-dialkyl-2-azaspiro[4.5]deca-1,6,9-trien-8-ones. The stability of the latter toward the dienone-phenolic rearrangement depends on the nature of the substituent R. The reaction mechanism was studied by the semiempirical quantum-chemical AM1 method.     

Regioisomerism in the Ritter reaction. 1. Synthesis of 3,3,5,6,7-, 3,3,6,7,8-, 3,3,5,7,8-, and 3,3,5,6,8-pentamethyl-3,4-dihydroisoquinolines from 1,2,3- and 1,2,4-trimethylbenzenes

Reactions of 1,2,3- or 1,2,4-trimethylbenzene with isobutyraldehyde and ethyl cyanoacetate (ECA) or reactions of the corresponding 1-aryl-2-methylpropan-1-ols with ECA afforded isomeric 3,3,5,6,7-, 3,3,6,7,8-, 3,3,5,7,8-, and 3,3,5,6,8-pentamethyl-3,4-dihydroisoquinolines. Isomerization is explained as the ring opening of a spiran intermediate in two possible ways followed by the Jacobsen rearrangement.     

Nickel-catalyzed, cascade cycloadditions of 1-ethynyl-8-halonaphthalenes with nitriles: synthesis, structure, and physical properties of new pyrroloarenes

The reaction of 1-ethynyl-8-halonaphthalenes 1 with nitriles in the presence of the catalytic system [NiBr(2)(dppe)]/Zn (dppe=1,2-bis(diphenylphosphino)ethane) is found to produce unusual pyrroloarenes 2. The carbon-nitrogen triple bond in nitrile is activated twice, and five new bonds are formed in a one-pot transformation, which causes a pyrrole and two six-membered rings to be generated simultaneously. The scope and limitations of this reaction are examined. Similarly, alkyl-bridged diynes also furnish the corresponding polycycles. Diaryl-substituted cycloadducts 2 (R(1)=Ar) are fluxional, because of the restriction in rotation of the aryl groups. The rotational barrier is studied by performing (1)H NMR experiments at various temperatures. The structures of several compounds are determined by X-ray crystallographic analysis. The photophysical and electrochemical properties of the pyrroloarenes are also investigated.     

Spirocyclohexadienones: X. Three-component condesation of 1,2,3- and 1,2,4-trimethoxybenzenes with cyclohexanecarbaldehyde and nitriles. Synthesis of 1,2- and 1,4-dimethoxy-14-azadispiro[5.1.5.2]pentadeca-1,4-dien-3-ones

Substituted 1,2- and 1,4-dimethoxy-14-azadispiro[5.1.5.2]pentadeca-1,4-dien-3-ones and 1,2(1,4)-dimethoxy-14-azadispiro[5.1.5.2]pentadeca-1,4,14-trien-3-ones were synthesized by three-component condensation of cyclohexanecarbaldehyde with 1,2,3- or 1,2,4-trimethoxybenzene and the corresponding nitriles in the presence of concentrated sulfuric acid.     

Three-component condensation of 2-naphthylamine with aromatic aldehydes and 5-(2-furyl)-1,3-cyclohexanedione

Three-component condensation of 5-(2-furyl)-1,3-cyclohexanedione with 2-naphthylamine and aromatic or heteroaromatic aldehydes afforded 12-aryl(hetaryl)-9-(2-furyl)-7,8,9,10,11,12-hexahydrobenzo[a]-acridin-11-ones possessing two asymmetric carbon atoms (C⁹ and C¹²). The products were found to be formed as mixtures of diastereoisomers.     

Three-component condensation of hetarylguanidines with aldehydes (ketones) and dicarbonyl compounds

The three-component condensation of benzoxa(thia)zolylguanidines, aldehydes (ketones), and β-dicarbonyl compounds (acetyl-and benzoylacetone, ethyl acetoacetate, acetoacetanilides, cyclohexanedione-1,3 and its derivatives) has been studied. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, 1549–1554, October 2006.     

Sulfenyl halides in the synthesis of heterocycles. 3. Interaction of perfluoro-1-ethyl-2-methyl-1-propenyl-iminochloromethanesulfenyl chloride with 1-allyl-2-methoxybenzene

Reaction of perfluoro-1-ethyl-2-methyl-1-propenyliminochloromethanesulfenyl chloride with 1-allyl-2-methoxybenzene in methylene chloride and nitromethane gives as the main products β-and β-chloro sulfides plus derivative of 2,3-dihydrobenzofuran. The reaction in nitromethane in the presence of lithium perchlorate gave a product of addition of sulfur-containing electrophiles to the double bond-a derivative of 1,3-thiazolidin-2-one-in preference to the cycloaddition product. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, 1558–1564, October, 2006.     

Cp2TiCl2-catalyzed synthesis of tetraalkyl-substituted pyrazines by the reaction of nitriles with EtAlCl2 and Mg

Tetraalkyl-substituted pyrazines were obtained by the multicomponent reaction of aliphatic linear nitriles with EtAlCl₂ in the presence of Mg and Cp₂TiCl₂ catalyst in 60–91% yields. The same processing of isobutyronitrile gave 2,4,5-triisopropyl-1H-imidazole in 56% yield.     

Condensed isoquinolines. 19. Synthesis of 1′-R-spiro[6a,11b-diazabenz[e]aceanthrylene-6(7H),4′ (1′H)-pyridine]-5,7(12H)-diones

During acylation of 7-isonicotinoyl-6,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-one or its alkylation followed by treatment with organic bases, spirocyclization occurs with formation of derivatives of a novel heterocyclic system: 1′-acyl-and 1′-alkylspiro[7H,12H-6a,11b-diazabenz[e]aceanthrylene-6(5H),4′(1′ H)-pyridine]-5,7-diones. We have studied the spectral properties of the synthesized spirans. We have shown that 7-nicotinoyl-6,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-one does not undergo an analogous reaction of repeated acylation, while treatment of its quaternary salt with bases leads to a complex mixture of unidentified products. For Communication 18, see [1]. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 113–122, January, 2006.     

Reactions of cyclochlorotriphosphazatriene with 2-mercaptoethanol. Calorimetric and spectroscopic investigations of the derived products

Abstract

The reactions of hexachlorocyclotriphosphazatriene, N₃P₃Cl₆ (1) with 2-mercaptoethanol, 2-HS-CH₂-CH₂-OH (2), in (1:1, 1:2 and 1:3) mole ratios, in excess of NaH, in THF and diethylether solutions yield a total of 6 novel products: one mono spiro, N₃P₃Cl₄[O-CH₂-CH₂-S] (3); one mono-substituted open chain, N₃P₃Cl₅[S-CH₂-CH₂-OH] (4); one dispiro, N₃P₃Cl₂[O-CH₂-CH₂-S]₂ (5); one tri-substituted open chain, N₃P₃Cl₃[S-CH₂-CH₂-OH]₃ (6); one tris-spiro, N₃P₃[O-CH₂-CH₂-S]₃ (7) and one disubstituted open chain, N₃P₃Cl₄[S-CH₂-CH₂-OH]₂ (8) derivatives. The spiro products (3, 5 and 7) are formed as the major products in this system and all of the synthesized compounds are found to be stable at room temperature. The structures of the derived compounds were elucidated by elemental analysis, TLC-MS, ³¹P and ¹H NMR spectral data. For evaluation of melting behavior of derivatives (6) and (7), thermal transition peaks and their corresponding enthalpies were determined via DSC technique.     

2-Substituted nitrones and isomeric hydroxylamines - obtained via aluminium amalgam reduction of nitro nitriles and ketones—a new access to convenient intermediates for nitroso carbonyl compounds preparation

Substituted five-membered cyclic nitrones (pyrroline N-oxides) have been obtained in good to high yields from tertiary γ-nitro ketones and nitriles employing aluminium amalgam as a reducing agent in moist diethyl ether or THF. Attempts to obtain cyclic amino nitrones from α- or β-nitro nitriles failed and only the corresponding hydroxylamines have been isolated. Both nitrones and hydroxylamines have been used for synthesis of tertiary C-nitroso nitriles or ketones.     

Design of TiO2@graphene nanosheets with rough surface and its reinforcement to polyarylene ether nitriles

The interfacial interaction is extremely important when dealing with filler‐reinforced polymer materials. Herein, in order to improve the interfacial interaction with the polyarylene ether nitriles (PEN) matrix, a three‐dimensional rough structure was designed. First, needle‐like TiO₂ nanocrystals were grown on each surface of the graphene. Morphology analysis proved that rough TiO₂ nanocrystals were coated on the graphene nanosheets. Then, TiO₂@graphene/PEN composites were fabricated to investigate the filler–matrix interaction. Thereafter, the different polymer chains could be interlocked by the TiO₂ “needles” when the rough TiO₂@graphene was embedded into the polymer resin. The surrounding PEN polymer chains (work as ropes) could tie to the “needles” (work as wood pile). That is to say, the effective polymer chain length was greatly lengthened, resulting in the improvement of interfacial interactions and mechanical properties. Most importantly, the morphology, mechanical and rheological tests of the composites also proved the improvement of interfacial interactions and mechanical properties. Copyright © 2015 John Wiley & Sons, Ltd.