| The versatility and high reactivity of the2-thiazolines makes them attractive intermediates for the synthesis of many types of organic molecules, such as carbonyl, thiazoles, amino thiols, or thiazolinium salts. Moreover, thiazolines have been utilized as asymmetric catalysis ligands in the chiral synthesis. A lot of synthetic thiazolines have found biological applications as antibiotics, antitumor agents, etc. Several naturally occurring thiazolines have been shown to antitumor activity and exhibit antibiotic. So far, various of methods for the preparation of thiazolines have been reported. In recent years, we have been devoting our efforts towards the application of fluoroalkanesulfonyl fluorides (RfSO2F) in organic synthesis. for example, to induce epoxidation of vicinal dihydroxyl compounds and induce azirination of vicinal N-Tosyl amino alcohols. In this thesis, we report the result of RfSO2F-induced cyclodehydration of vicinal N-thioacetyl amino alcohols resulting in the smooth formation of corresponding2-thiazoline derivatives.This work contained the following three aspects:1、the preparation of and synthetic applications of thiazolines were reviewed.2、the reaction of N-thioamides vicinal amino alcohols with fluoroalkanesulfonyl fluoride in the presence of triethylamine or1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) as base was described in details. Thus, an efficient one-step preparation of2-thiazolines via RfSO2F-induced cyclodehydration of vicinal amino alcohols at room temperature was developed. This protocol has the advantages of readily availability of starting materials, labile work-up, mild conditions and broad application scope, etc.3、We optimized the reaction conditions and studied its application scope. Through analysis of experimental phenomena and results, we proposed a reasonable mechanism to interpret the cyclodehydration of vicinal N-thioacetyl amino alcohols mediated by RfSO2F. |
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