| Carbon-hydrogen bonds are ubiquitous in organic compounds and natural products, Compared with traditional organic synthesis, there is a great advantage using direct transformations through C-H functionalization reaction. This method not only reduces the synthetic steps, lowers the waste emissions, and improves the atom utilization, but also increases the reaction efficience. Hence, the C-H functionalization reaction has attracted much attentions and made great development in recent years. Generally, with the help of directing groups and electron effects, this kind of reaction can selectively form C-C bond and C-X bond (X=O, N, S, Cl, Br, I ect). With respect to C-H functionalization C-C bond formation, there are many reports and detailed mechanism. However, it remains to be a big challenge about C-H functionalization via C-X bond formation. In this dissertation, we mainly investigate the C-O bond formation by directed C-H functionalization and acylation of C-H functionalization in heterocyclic compounds.1. The intermolecular ortho C-H alkoxylation of anilides was accomplished using Pd(OAc)2 as the catalyst and K2S2O8 as the oxidant. The usage of 0.2 equiv of CH3SO3H was very important, it not only improves the reaction, but also makes the reaction proceed in mild conditons mostly. A series of secondary alcohols could also react smoothly with anilides to give the desired product except primary alcohols, greatly expanding the scope of alcohol in alkoxylation reaction.2.3-Acylindoles could be obtained through direct acylation of free (N-H) indoles with nitriles using Pd(OAc)2/bipy as the catalyst and D-CSA as the additive. Compared with traditional synthesis of 3-acylindoles, this method was simplely operated and could afford many 3-acylindoles from indoles with commercially available nitriles.3.2-Acylthiophenes could be effectively obtained through direct acylation of thiophenes with nitriles using Pd(OAc)2/bipy as the catalyst and D-CSA as the additive. |
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