| Unexpected Synthesis of Ethyl 4-mercapto-3-oxobutanoate |
| کد مقاله : 1142-ICOC |
| نویسندگان |
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رویا سلیم زاده *1، حمزه کیانی2، مصطفی ریاحی2 1دانشجوی دانشگاه شهرکرد 2هیات علمی دانشگاه شهرکرد |
| چکیده مقاله |
| Introduction: Mercapto-containing compounds are of great interest in the development of valuable active structures. They are used in food as flavoring additives. Sulfur-containing molecules have been identified as powerful aroma compounds in various fruits, beverages, and foods, including tropical fruits, guavas, passionfruit, durian, grapefruit, sesame oil, onion (Allium cepa L.), garlic (Allium sativum), cheddar cheese, barbecue, processed foods, meat, coffee, and beer. Thiols are the most potent of the 230 known key food odorants, due to their olfactory responses, in general, and their very low odor thresholds on the order of picograms per liter. Thiols play an exceptional role in human olfaction. Furthermore, thiol compounds play a prominent role in the construction of proteins, pharmaceuticals, biological molecules, and materials [1-6]. Methods: The two precursors, ethyl 4-chloro-3-oxobutanoate (1) and 2-mercaptobenzimidazole (2), were reacted together in acetonitrile solvent. In this reaction, potassium carbonate was also used as a base. The reaction was carried out under reflux conditions for 6 h. After the reaction was completed, the mixture was cooled to room temperature, and the resulting product was separated via filtration and purified. Results: To synthesize ethyl 4-((1H-benzo[d]imidazol-2-yl)thio)-3-oxobutanoate (3), the reaction of ethyl 4-chloro-3-oxobutanoate (1) and 2-mercaptobenzimidazole (2) was carried out in the presence of K2CO3 (Scheme 1). The aim was to synthesize compound 3. Similar reactions of the thiol group leading to the alkylation of the sulfur moiety were reported in the literature. In the present reaction, after purification and identification, it was determined that alkylated compound 3 was not obtained. Analysis of the IR and NMR spectra showed that ethyl 4-mercapto-3-oxobutanoate (4) was formed, contrary to expectations. This was an interesting and unexpected result, which is a promising result from a synthetic point of view. The reaction in EtOH and acetone did not lead to satisfactory results, but in CH3CN, good results were obtained. Conclusion: The new method for the synthesis of ethyl 4-mercapto-3-oxobutanoate (4) is presented. The results of studies using several solvents and different temperature conditions showed that the optimal conditions for carrying out the reaction were refluxing acetonitrile in the presence of potassium carbonate |
| کلیدواژه ها |
| Keywords: Ethyl 4-mercapto-3-oxobutanoate, Ethyl 4-chloro-3-oxobutanoate, 2-Mercaptobenzimidazole |
| وضعیت: پذیرفته شده |