Condensation of N-(piperidylidene-4)arylamines with acetylenedicarboxylic esters

The substituted piperidines, N-(piperidin-3-en-4-yl)-N-(1,2-dimethoxycarbonyl-etheno)arylamine and 1-aryl-3,4,5,6-tetramethoxycarbonyl-1,2-dihydrospiro[cyclo-[pyridine-2,4-piperidine], were synthesized by the condensation of acetylenedicarboxylic ester with an azomethine, obtained from a -piperidone. It was found that the amounts of 11 and 12 addition compounds obtained depends on the ratio of starting reagents. Compounds isomeric at the vinyl group were examined in the case of one of the 11 addition compounds. N-(1,2,5-trimethylpiperidin-4-yl)-N-(1,2-dimethoxycarbonyletheno)aniline was prepared by two methods.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 943–946, July, 1986.     

Syntheses of alkyl (E)-(1-aryl-2-pyrrolidinylidene)acetates

Two methods for the synthesis of the title compounds [3] are presented. The first, and less satisfactory, method uses the sulphide contraction, which involves salt formation between alkyl bromoacetates and N-arylpyrrolidine-2-thiones [2] followed by sulphur extrusion. By-products include N-arylpyrrolidin-2-ones [1] and 3-alkoxycarbonylmethylpyrrolidine-2-thiones [5]. A better route is by way of condensation between ethyl 6-chloro-3-oxohexanoate [6] and substituted anilines, followed by intramolecular cyclisation. An unusual Reformatsky reaction with methyl bromoacetate and 1-phenylpyrrolidine-2-thione [2a] is also reported.     

Synthesis of Derivatives of (4-Methyl-2-Quinolylthio)acetic and (4-Methyl-2-Quinolylthio)propionic Acids

An efficient synthesis has been developed for derivatives of (4-methyl-2-quinolylthio)acetic and (4-methyl-2-quinolylthio)propionic acids by the reaction of 4-methyl-2-thioxoquinoline with methyl methacrylate, the amide of methacrylic acid, acrylonitrile, ethyl bromoacetate, and ethyl acrylate. The hydrolysis of the resultant intermediates by (quinolylthio)acetic and (quinolylthio)propionic acids gave the corresponding acid products, which are also formed in the reaction of 4-methyl-2-thioxoquinoline with chloroacetic and acrylic acids. The reaction of 4-methyl-2-thioxoquinoline with allyl bromide was studied. The potassium permanganate oxidation of the resultant 2-allylthio-4-methylquinoline led to (4-methyl-2-quinolylthio)acetic acid.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 403–406, April, 2005.     

Reactions of N- and C-Alkenylanilines: III. Synthesis and Cyclization of Substituted 2-(1-Methyl-2-butenyl)anilines

Reactions of substituted 2-(1-methyl-2-butenyl)anilines with iodine result in cyclization and formation of 3-iodo-1,2,3,4-tetrahydroquinolines; N-methylsulfonyl-2-(1-methyl-2-butenyl)anilines give rise exclusively to the corresponding 2-(1-iodoethyl)-3-methyl-2,3-dihydroindoles.     

Molecular Structure of Complexes with Bifurcated Hydrogen Bond: I. N-(4-Methyl-2-nitrophenyl)acetamide

According to the results of HF/6-31G* and B3LYP/6-31G* nonempirical calculations, N-(4-methyl- 2-nitrophenyl)acetamide in the synperiplanar and antiperiplanar conformations gives stable complexes with protophilic solvents, which are stabilized by bifurcated (three-center) hydrogen bond. The complexes are characterized by (1) opposite variations of the interatomic distances and angles corresponding to intra- and intermolecular components of the bifurcated hydrogen bond, (2) extension of the intramolecular component and a more pronounced shortening of the intermolecular component with increase in the strength of the three-center H-complex, and (3) nonlinear and nonmonotonic relation between the NH stretching vibration frequency and the energy of complex formation.     

Synthesis of 6-Methyl-4-(1-methyl-2-buten-1-yl)-2-(2-cyclohexen-1-yl)- and 6-Methyl-4-(1-methyl-2-buten-1-yl)-2-(1-cyclohexen-1-yl)anilines

Alkenylation of 6-methyl-2-(2-cyclohexen-1-yl)- and 2-(1-cyclohexen-1-yl)anilines with piperylene in the presence of AlCl₃ and transformation of the resulting cyclohexenylanilines into carbazole structures were studied.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 441–443.Original Russian Text Copyright © 2005 by Gataullin, Ishberdina, Sotnikov, Abdrakhmanov.     

1-Methyl-3-piperidone and 1-methyl-3-pyrrolidone derivatives from a dieckmann reaction

Attempts to prepare 1-methyl-5-carbethoxy-3-piperidone by a Dieckmann cyclization led to formation of its diethyl ketal on workup. The five-membered ring system, 1-methyl-4-(ethoxy-carbonylmethyl)-3-pyrrolidone was also formed in the cyclization.     

Condensation Op 3-Acetyl-and 3-Acetyl-4-Methyl-2H-1-Benzopyran-2-One with Aromatic Adehydes

The reactivities of 3-acetyl-2H-1-benzo-pyran-2-one (2) and 3-acetyl-4-methyl-2H-1-benzopy-ran-2-one (3)are compared in the condensation with aromatic aldehydes. It is established that the benzopyrones 2 and 4 condense with various aromatic aldehydes in chloroform containing some drops of piperidine by boiling for 7 hours and azeotropic distillation of water, yielding 3-cinnamoyl-2H-1-benzopyran-2-ones (3a-g) and 4-(2-arylvinyl)-3-acetyl-2H-1-benzopyran-2-ones (6a-f), respectively. Evidence is provided that benzopyrone 4 participates in the condensation with the methyl group in position 4. A probable mechanism of the process is proposed.     

Synthesis,Crystal Structure and Antifungal Activities of 3-Methyl-1-(4-methylphenyl)-4-(N-4-trifluoromethylphenyl)-aminomethyl-5-(4-methoxyphenylthio)-1H-pyrazole

The title compound 3-methyl-1-(4-methylphenyl)-4-(N-4-trifluoromethylphenyl) aminomethyl-5-(4-methoxyphenylthio)-1H-pyrazole has been synthesized via a four-step reaction and characterized by IR,1H NMR,elemental analysis and X-ray crystallography.The compound crystallizes in monoclinic,space group P21/c with a = 8.7170(15),b = 18.355(3),c = 15.292(3) ,β = 103.445(3)°,V = 2379.7(7) 3,Dc = 1.350 g/cm3,Z = 4,μ = 0.184,F(000) = 1008,and the final R = 0.0491 and wR = 0.1339 for 4160 observed reflections(I 2σ(I)).The results demonstrate that there is a face-to-face π-π stacking interaction between one benzene ring(C(19)~C(24)) and another(C(13)~C(18)) at a plane-plane distance of 3.3539 .The ring normal and vector between the ring centroids form an angle of 18.2o up to the centroid-to-centroid distance of 3.5273 .The crystal structure is stabilized by the intermolecular hydrogen bond of N(3)-H(3A)···N(2)(symmetry code:A –x+1,–y+1,–z).The preliminary biological test shows that the title compound has a moderate antifungal activity.