| Amino-azoles are very important structural units in many natural products and other biologically active compounds. And they also exhibit a wide range of pharmacological and physiological activities. Currently, the most important and widely used synthetic method is Pa-or Cu-catalyzed cyclization, coupling and so on. However, these procedures usually suffer from high catalyst loadings, the formation of hydrohalic acid as by-product and low atom efficiency.In the second chapter, the regioselective N-alkylation of2-aminobenzothiazoles with benzylic alcohols to2-(N-alkylamino)benzothiazoles catalyzed by CuCl/NaOH was explored for the first time. Then, expanded the scope of the reaction, in all case, no side product was observed. Clearly, the reaction exhibited complete regioselectivity. It was also note worthy that the substituent such as halide, methoxyl, thiomethyl, trifluoromethyl or trifluoromethoxy group on either benzyl alcohols or2-aminobenzothiazoles could be tolerated under this reaction conditions.In the third chapter, we researched the regioselective N-alkylation to synthetic2-(N-alkylamino)thiazoles and2-(N-alkylamino)oxazoles catalyzed by [Cp*IrCl2]2/NaOH systerm for the first time. The procedure is apparently attractive from a synthetic point of view because of high atom efficiency, the formation of water as only side product, and broad substrate scope.In the forth chapter, we developed the first example of the preparation of2-(N-alkylamino)imidazoles by direct N-alkylation of the corresponding2-aminoimidazoles with alcohols catalyzed by [Cp*IrCl2]2/K2CO3systerm. And verified the reaction mechanism. This Iridium-catalyzed regioselective reaction has advantages over existing methods, such as the ready availability of starting materials, high atom efficiency, and environmental friendliness.This research will open up new fields for "hydrogen auto-transfer reaction" and facilitate the progress of green chemistry-directed reaction in organic synthesis. |
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