Synthesis and transformations of ethyl 3-amino-4-oxo-4H-quinolizine-1-carboxylateTrajkovski, Aleksandar (Avtor) Svete, Jurij (Mentor) 4-oxo-4H-quinolizineaminediazonium saltsdecarboxylationIn this diploma work, an attempt to synthesize ethyl 3-amino-4-oxo-4H-quinolizine-1-carboxylate (44) has been made. The proposed methodology of the synthesis includes cyclization of methyl 2-benzamido-3-(dimethylamino)propenoate (42) and ethyl 2-(2-pyridyl)acetate (41) under acidic conditions followed by further hydrolysis of benzamido group in the cyclized product, ethyl 3-benzamido-4-oxo-4H-quinolizine-1-carboxylate (43). Although the first step was successful, the hydrolysis did not proceed as planned, since hydrolysis of the ester group and subsequent decarboxylation accompanied the hydrolysis of the amide group. Consequently, 3-amino-4-oxo-4H-quinolizine (45) was obtained as the product. The last step of this work was an attempt to convert the hydrolysed amine into the respective diazonium salt 47 by diazotation with sodium nitrite under acidic conditions. This attempt was only partially successful, since unknown impurity 48 was present along with the desired product in a 1:4 molar ratio. 20232023-06-27 07:00:00Diplomsko delo/naloga147222sl