• Title/Summary/Keyword: alkyl halides

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A Versatile Synthesis of α-Keto (cyanomethylene)triphenylphosphorane Ylides from Alkyl Halides Utilizing a Noble Phenylsulfonyl Reagent

  • Lee, Kieseung;Hwang, Chan-Yeon
    • Bulletin of the Korean Chemical Society
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    • v.34 no.10
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    • pp.2953-2958
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    • 2013

  • A noble phenylsulfonyl reagent 8 having ${\alpha}$-oxo (cyanomethylene)triphenylphosphorane ylide subunit readily condensed with various alkyl halides under basic conditions to afford ${\beta}$-alkyl-${\alpha}$-oxo-${\beta}$-phenylsulfonyl (cyanomethylene)triphenylphosphorane ylides 9 in excellent yields. These sulfonyl ylides 9 were then reductively desulfonylated with $Na(Hg)/Na_2HPO_4$ in the presence of methanol to provide ${\alpha}$-keto (cyanomethylene)-triphenylphosphorane ylides 2' in good to excellent yields. Our new synthetic approach offers an expeditious access to various ${\alpha}$-keto (cyanomethylene)triphenylphosphorane ylides from alkyl halides utilizing a new phenylsulfonyl reagent as the key reagent under mild reaction conditions in good overall yields.

  • https://doi.org/10.5012/bkcs.2013.34.10.2953 인용 PDF KSCI

Synthesis and Antimicrobial Activity of Some New 1-Alkyl-2-alkylthio-1,2,4-triazolobenzimidazole Derivatives

  • Mohamed, Bahaa Gamal;Hussein, Mostafa Ahmed;Abdel-Alim, Abdel-Alim Mohamed;Hashem, Mohammed
    • Archives of Pharmacal Research
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    • v.29 no.1
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    • pp.26-33
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    • 2006

  • Some new derivatives of 1,2,4-triazolo[2,3-a]benzimidazoles were synthesized through the reaction of 1,2-diaminobenzimidazole with carbon disulfide. The resulting 1,2,4-triazolo-[2,3a]benzimidazole-2-thione intermediate was reacted with one equivalent of alkyl halides to give the corresponding 2-alkylthio derivatives, which were further alkylated through the reaction with another one equivalent of different alkyl halides to afford the target compounds; 1-alkyl-2alkylthio-1,2,4-traizolo[2,3-a]benzimidazoles. On the other hand, the 1,2-disubstituted derivatives with two identical alkyl substituents were prepared by the reaction of 1,2,4-triazolo[2,3-a]benzimidazole-2-thione with two equivalents of the alkyl halides. The structures of the new compounds were assigned by spectral and elemental methods of analyses. The synthesized compounds were tested for their antibacterial and antifungal activities. Most of the tested compounds proved comparable results with those of ampicillin and fluconazole reference drugs. The study indicated that, the antibacterial as well as the antifungal activities of the test compounds were improved with increase in the bulkiness of the introduced alkyl groups. Also, some active antibacterial compounds were tested for their antimycobacterial activity. All the test compounds showed equipotent antitubercular activity as that of INH as a reference drug.

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Reduction of Alkyl Halides by Homonuclear Bridging Hydride, (μ-H)[(η$^5-MeCp)$Mn(CO)₂]₂-ppn+

  • 박용광;김영웅
    • Bulletin of the Korean Chemical Society
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    • v.17 no.3
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    • pp.269-273
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    • 1996

  • Alkyl halides were reduced to the corresponding alkanes by the homonuclear bridging hydride, (μ-H)[(η5-MeCp)Mn(CO)2]2-PPN+ in THF at the elevated temperatures (40-60 ℃) under the pseudo first order reaction conditions where excess of alkyl halide was employed under nitrogen atmosphere. The reaction is of overall second order; first order with respect to [bridging hydride] and first order with respect to [alkyl halide] with the activation parameters, ΔH≠=28.93 kcal/mol and ΔS≠=17.95 e.u. The kinetic data, the ESR evidence and the reaction with cyclopropyl canbinyl bromide ensure that two possible reaction pathways are operable in this reaction: (1) concerted mechanism, and (2) single electron transfer pathway are in competition leading to the same product, the corresponding alkane.

  • https://doi.org/10.5012/bkcs.1996.17.3.269 인용 PDF

N-Alkylation of Primary Aromatic Amines Using Alkylhalide and Triethylamine (알킬할라이드와 Triethylamine을 이용한 일급 아로미틱 아민의 N-알킬레이션)

  • Kim, Ju-Hee;Park, Myung-Sook
    • YAKHAK HOEJI
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    • v.49 no.2
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    • pp.162-167
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    • 2005

  • Synthetic method for the selective N-monoalkylation of anilines using alkyl halides and triethylamine under room temperature was described. The corresponding N-alkyl anilines were obtained in good yields with minor quantities of dialkylated products. Anilines 2a-m and 3a-m were identified using NMR and IR. A series of 2a-m and 3a-m has been synthesized from aniline, toluidines, ethylanilines, aminoacetophenones, phenetidines. Formation of anilines was undertaken with dropping of alkylhalides at room temperature in methanol (or ethanol) for 3 hours~5 days. Selectivity on the monoalkylation was relatively high. Synthetic ratio of monoalkylated and dialkylated product was 94 : 6 in case of maximum monoalkylation.

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