(1)One-pot Synthesis of Thioesters with Bunte Salts as a Sulfur Surrogate under Transition Metal-Free Conditions(2)Hexamethyldisilazane Promoted C-N Bond Formation via Thioesters: Synthesis of Benzamides and Dimethylformamidines

• Main Authors: Yen-Sen Liao, 廖彥森
• Other Authors: Chien-Fu Liang
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/2am6n9

碩士 === 國立中興大學 === 化學系所 === 106 === In the first part of this thesis, we reported a convenient method of one-pot synthesis of thioesters by using odorless sodium thiosulfate, various anhydrides and organic halides. Compared with traditional method, this method did not use thiols, which possessed malodorous flavors and easily oxidized to form the disulfide bond. This synthetic method was firstly using organic anhydrides and sodium thiosulfate to form the Bunte salts, followed by reacting with organic halides to generate thioesters. Furthermore, two important organic compounds could be successfully synthesized using the developed method. It was worth to mention that our system was transition metal-free conditions and easy applicability to the large-scale operation. In the second part of this thesis, we developed a new method for the synthesis of primary amides by using thioesters and hexamethyldisilazane (HMDS). Compared with reported literatures, the developed methods were performed under metal-free conditions. In our synthetic strategy, we found that the hexamethyldisilazane in N,N-dimethylformamide (DMF) under heating conditions will be formed amidine, then reacted with thioesters to form the primary amide and dimethylformamidine. Moreover, primary amide and dimethylformamidine can be synthesized individually by adjusting the amounts of hexamethyldisilazane. In addition, we designed the control experiment to prove the formation of amidine by proton (H) and carbon-13 NMR spectrums. The advantages of this synthetic method were structurally diverse products, use of relatively cheap reagents, and easy applicability to large-scale operation.