Fluoroazoles. II. Synthesis and 1H and 19F Nmr spectra of 2-, 4-, and 5-Fluoro-1-methylimidazole

The three possible ring-monofluorinated N-methylimidazoles have been prepared by photochemical irradiation of the corresponding diazonium tetrafluoroborates. 5-Fluoro-1-methyl-imidazole was also obtained by methylation of 1-acetyl-4-fluoroimidazole. The ¹H and ¹⁹F nmr spectra of these N-methylated fluoroazoles are compared, and the predominance of one tautomeric form in 4(5)-fluoroimidazole is discussed.     

Fluoroazoles. III. Synthesis and 1H and 1–9F nmr spectra of 3-, 4-, and 5-fluoro-1-methylpyrazole

The three monofluoro derivatives of N-methylpyrazole have been synthesized. 3-Fluoro-1-methylpyrazole and 4-fIuoro-1-methylpyrazole were prepared from the appropriate amines by diazotization and photochemical irradiation of the diazonium salts in tetrafluoroboric acid. 5-Fluoro-1-methylpyrazole was obtained from 1-acetyl-3-fluoropyrazole and methyl fluorosulfonate, and also by direct methylation of 3(5) fluoropyrazole with dimethyl sulfate. The ^1–9F chemical shifts of these N-methylated fluoroazoles cover a great range (ca. 50 ppm) and show a good correlation with the chemical shifts of H₃, H₄, and H₅ protons of 1-methylpyrazole. An unexpected long-range coupling ⁵J (F-CH₃) is observed in 3-fluoro-1-methylpyrazole.     

Syntheses of new 1,2-, 1,3-, and 1,4-diazine derivatives. 1. Synthesis of diazinylarylacetonitriles

A number of diazinylarylacetonitriles were obtained in the reactions of properly substituted 3-chloropyridazine, 2-chloropyrimidine, or 2-chloropyrazine derivatives with various arylacetonitriles. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1346–1354, September, 2006.     

Maillard Polymers Derived from D-Glucose-1 and -6-14C,Glycine-1 and -2-14C,and C-1-, and Methyl-14C Methionine

Maillard polymers were prepared from D-glucose-1 and -6-14C, glycine-1 and -2-¹⁴C, as well as C-1 and methyl-¹⁴C methionine, and the activities of the isolated polymers measured as a function of time. In both cases, C-1 of the amino acids were incorporated at the lowest levels, with D-glucose carbon atoms at the highest levels. The data support the conclusions that carbon dioxide, produced during the Maillard reaction, arises from C-1 of the amino acids, but also suggests that other carbons of the amino acids may contribute as well.     

Author Index Vol.32,Nos.1-12,2014

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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.     

Syntheses of 1-, 2-, 3- and 4-acridinecarbaldehydes

The four acridinecarbaldehydes, namely, acridine-1-carbaldehyde, acridine-2-carbaldehyde, acridine-3-carbaldehyde, and acridine-4-carbaldehyde have been synthesized for the first time.     

1, 2-, 1, 3- and 1, 4-Cyclohexanedicarboxylates of Cd and Mn with chain and layered structures

A systematic study has been carried out on the three isomeric cyclohexanedicarboxylates (CHDCs) formed by cadmium and manganese with the three isomeric dicarboxylic acids, in the presence or absence of amines. The CHDCs have been prepared under hydrothermal conditions and their structures established by X-ray crystallography. We have been able to isolate two-dimensional layered structures of 1,2-, 1,3- and 1,4-cyclohexanedicarboxylates and chain structures of 1,3- and 1,4-cyclohexanedicarboxylates. The infinite metal-oxygen-metal linkages are observed only in the case of the 1,2-dicarboxylate. In all the three isomeric cyclohexanedicarboxylates, the e,e conformation is most favored, although the 1,4-CHDCs often contain rings in both the e,e and the a,e conformations.     

Synthesis, Structure and Biological Activities of 2-（1H- 1,2,3-Benzotriazol-1 -yl ）-1-（ 4- methylphenyl ）-2-（1H-1,2,4-triazol-l-yl）-1-ethanone

The title compound was synthesized and characterized by IR, ^1H NMR, elemental analysis and single crystal X-ray diffraction analysis. Its biological activities were also tested. The results show that the title compound reveals inhibiting activities towards wheat gibberellin, apple ringspot, tomato early blight, peanut cercospora arachidicola and stem wilt of asparagus.     

1-R-2-[(1E,3E)-4-Aminobuta-1,3-dien-1-yl]-1H-benzimidazoles. Synthesis and some transformations

7-Nitropyridobenzimidazolium salts are cleaved with secondary amines to form 2-[(E,E)-4-aminobuta-1,3-dienyl]-1H-benzimidazoles. The latter react with dimethyl acetylene-dicarboxylate to yield 4a-[(E,Z,E)-6-amino-4,5-dimethoxycarbonylhexa-1,3,5-trien-1-yl]-1,2,3,4-tetra(methoxycarbonyl)-4a,5-dihydropyrido[1,2-a]benzimidazoles.     

Heteroatomic derivatives of aziridine. 14. Reactions of 1-(carbomethoxyethyl)-, 1-[1,2-bis(carbethoxy)ethyl]-, and 1-[1,2-bis(carbomethoxy)vinyl]aziridine with thiols, 1,2-ethanedithiol,and thiolcarboxylic acids

The reactions of 1-(carbomethoxyethyl)-, 1-[1,2-bis(carbethoxy)-ethyl]-, and 1-[1,2-bis(carbomethoxy)vinyl]aziridine with thiols and thiolcarboxylic acids produce the corresponding sulfides and esters of S-substituted N-(2-mercaptoethyl) amino acids. The reaction of 1-[1,2-bis(carbethoxy)ethyl]aziridine with 1,2-ethane-dithiol results in the formation of {1,8-bis[1,2-bis(carbethoxy)-ethyl]amino}-3,6-dithiaoctane. Cyclization of the latter by condensation with phthaloyl chloride gives 9,10-benzo-8,11-dioxo-1,4-dithia-7,12-bis[1,2-bis(carbethoxy)ethyl]-7,12-diazacyclotetradec-9-ene.For report 13 see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1340–1342, October, 1984.