Applications Of Hypervalent Iodine Reagents In The Synthesis Methodology Of Heterocycles

Recently, hypervalent iodine reagents have been extensively used in synthetic organic chemistry. Hypervalent iodine reagents have attracted considerable attention of research for its good oxidation, such as the extremely mild reaction conditions required and its ability to oxidize chemoselectively a wide range of functionalities. The intramolecular N-N, S-N or C-C bond is formed through the hypervalent iodine reagents mediated oxidization process, and a new strategy is provided for the synthesis of heterocyclic compounds. Enaminones have emerged as an important synthetic intermediate because of its polyfunctional structural characteristics. Many nitrogen-containing heterocycles are prepared on the basis of enaminones.Combining with the research of hypervalent iodine reagents, enaminones and heterocyclic chemistry, we discussed the building of C-C bond and synthesis of heterocyclic compounds by using the oxidation of hypervalent iodine reagents.This work mainly based on the following two aspects:1.Using1.3-cyclohexanedione and different substituted aniline as starting materials, through the exploration of reaction condition, a series of3-(phenylamino)cyclohex-2-enone were synthesized as substrates.2. Using3-(phenylamino)cyclohex-2-enone as substrates, the C-C bond is formed and a series of carbazolone were synthesized via intramolecular cyclization in the presence of PIFA; a series of bimolecular coupling products were synthesized via the coupling reaction in the presence of PIDA. The structure of compounds were characterized by1H NMR and13C NMR.In summary, we proposed a new method which using enaminones as starting materials. involves the direct C-C bond formation to construct carbazolone via hypervalent iodine reagents mediated intramolecular cyclization, and mechanisms were studied for the reaction process. This protocol is associated with readily available starting materials, mild conditions, good yields, and broad range of synthetic potential of the products.