کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7609363 1493396 2017 25 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Impact of carbon dioxide solvent separators on the degradation of benzyl-2,3-dihydroxypiperidine-1-carboxylate during preparative supercritical fluid chromatographic purification
ترجمه فارسی عنوان
تأثیر جداسازهای حلال دی اکسید کربن بر تخریب بنزیل-2،3-دی هیدروکسی پپیدیدین-1-کربوکسیلات در خالص سازی کروماتوگرافی مایع سوپر کریستالی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
چکیده انگلیسی
During a preparative separation of the cis enantiomeric pair of benzyl-2,3-dihydroxypiperidine-1-carboxylate using supercritical-fluid chromatography (SFC) with methanol modifier, significant degradation of the products in the collected fractions was observed when a Waters SFC-350® (Milford, MA, USA) was used, but same was not observed when a Waters SFC-80q® (Milford, MA, USA) was used. Through a systematic investigation, we discovered that the compound degraded over time under an acidic condition created by the formation of methyl carbonic acid from methanol and CO2. The extent of the product degradation was dependent on the time and the concentration of CO2 remained in the product fraction, which was governed by the efficiency of CO2-methanol separation during the fraction collection. Hence, we demonstrated that the different designs of CO2-solvent separator (high pressurized cyclone in Waters SFC-350® and low-pressurized vortexing separator in Waters SFC-80q®®) had a significant impact on the degradation of an acid-sensitive compound. The acidity caused by CO2 in methanol was supported by diminished degradation after a nitrogen purging or after neutralizing the collected fractions with a base. Three different solutions to overcome the degradation problem of the acid sensitive compounds using SFC-350® with the high pressurized separator were investigated and demonstrated. The degraded products were isolated as four enantiomers and their relative stereochemistry were established based on 2D NMR data along with the plausible mechanism of degradation.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Chromatography A - Volume 1530, 29 December 2017, Pages 176-184
نویسندگان
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