کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6615021 459626 2013 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Electrochemical reduction of phthalide at carbon cathodes in dimethylformamide: Effects of supporting electrolyte and gas chromatographic injector-port chemistry on the product distribution
ترجمه فارسی عنوان
کاهش الکتروشیمیایی فتالید در کاتیدهای کربن در دی متیل فرمالید: اثرات الکترولیت و کروماتوگرافی گاز پیست اسید در مورد توزیع محصول
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
چکیده انگلیسی
Cyclic voltammetry and controlled-potential (bulk) electrolysis have been used to investigate the direct reduction of phthalide at carbon electrodes in dimethylformamide (DMF) containing 0.10 M tetramethylammonium perchlorate (TMAP) or tetra-n-butylammonium perchlorate (TBAP). Cyclic voltammograms recorded with a glassy carbon electrode exhibit a single cathodic peak and a corresponding anodic peak that arise, respectively, from one-electron reduction of phthalide to generate a radical-anion intermediate and from reoxidation of the intermediate. At a scan rate of 100 mV s−1, quasi-reversible behavior is observed (due to ring-opening of the radical-anion), whereas fully reversible behavior is seen at 5 V s−1 or higher. Digital simulation of cyclic voltammograms indicates that the lifetime of the radical-anion is 3.5 s. Bulk electrolysis of phthalide at a reticulated vitreous carbon cathode affords products that depend on the procedure used to analyze the catholyte. Direct injection of catholyte into a gas chromatograph shows phthalide and a 2-methylbenzoate ester bearing an alkyl moiety from the supporting-electrolyte cation. However, if the catholyte is partitioned between diethyl ether and aqueous hydrochloric acid before gas chromatographic analysis, phthalide and 2-methylbenzoic acid are observed. Thermally induced reactions that occur in the injector port of the gas chromatograph are responsible for the formation of the 2-methylbenzoate ester as well as for the phthalide found in all electrolyzed solutions.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Electrochimica Acta - Volume 113, 15 December 2013, Pages 557-563
نویسندگان
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