• Title/Summary/Keyword: Radical cyclization

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Synthesis of 2,5-Disubstituted Pyrrolidines from N-Alkenyl and Alkynyl N-Benzoyloxysulfonamides Catalyzed by (CuOTf)2･C6H6

  • Liu, Wei-Min;Liu, Zhen-Hong;Cheong, Wei-Wen;Priscilla, Lu-Yi Teo;Li, Yongxin;Narasaka, Koichi
    • Bulletin of the Korean Chemical Society
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    • v.31 no.3
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    • pp.563-569
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    • 2010

  • A new synthetic method of 2,5-disubstituted pyrrolidines is developed by the cyclization of unsaturated N-benzoyloxysulfonamides by $(CuOTf)_2{\cdot}C_6H_6$ in refluxing dichloroethane. Various N-4- and N-5-alkenyl and alkynyl N-benzoyloxysulfonamides are cyclized to give pyrrolidines. The cyclization proceeds via addition of sulfonamidoyl radicals to intramolecular unsaturated bonds or allylic hydrogen abstraction with the radical intermediates.

  • https://doi.org/10.5012/bkcs.2010.31.03.563 인용 PDF KSCI

Electrolytic Synthesis of 9-Methyl-2,3,6,7-tetramethoxyfluorene with Carbon Electrodes (카본전극을 이용한 9-Methyl-2,3,6,7-tetramethoxyfluorene의 합성)

  • Kim, Duk-Hyun
    • Applied Chemistry for Engineering
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    • v.8 no.1
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    • pp.39-48
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    • 1997

  • The intramolecular cyclization of 1,1-bis-(3,4-dimethoxyphenyl)ethane was shown to take place upon anodic oxidation at carbon electrodes in acetonitrile or in a solvent-mixture containing dichloromethane, trifluoroacetic acid(TFA). Yields are low in the former solvent due to the fact that the cyclized product (9-methyl-2,3,6,7-tetramethoxyfluorene) is more easily oxidized than it's precursor and the oxidation product is not stable. In the presence of TFA, the cation radical derived from the oxidation of the cyclized product is stabilized thus, after reduction may be isolated with better yields.

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Synthesis of Quinazoline 4-one Drvivatives from 2-Aminobenzamide(II) - Reaction with $\gamma$-Lactone and Diketone (2-Aminobenzamide로부터 Quinazoline 4-one 유도체의 합성 (II) - $\gamma$-락톤과 디케톤과의 반응)

  • 서명은
    • YAKHAK HOEJI
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    • v.30 no.5
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    • pp.203-207
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    • 1986

  • 2-Aminobenzamide reacts with not only keton radical but also carbonyl group in carboxylic acid, to form easily -N-C-N-novel ring cyclization as a result I and V. In addition, it reacts with 1, 2-cyclohexadione or benzil, whitch are both 1, 2-diketone compounds, at the both ketone radical sites to give V or VII respectively. On the reaction with dimethone, however, which has 1, 3-diketone radical, it reacted with only one carbanyl group and VI was produced. We investigated the reaction with cr-ketoester such as ethyl pyruvate and diethyl rnesoxalate. In the reaction with ethylpyruvate, amine group in 2-aminobenzamide reacted not with ketone radical but carbonyl group in ester (product VIII). On the other hand, diethyl measoxalate reacted at the ketone radical site rather than the ester site (product IX).

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