Palladium-Catalyzed Tandem Reactions For Constructing Muti-aryl Compounds

Organic photovoltaic materials have been developped rapidly in recent years and widely ultilized in some field in the future. The cost of synthesis of materials was a key to its commercial application. The conjugated structure in muti-aryl compounds is beneficial for the transportion of electrons. Therefore, most of organic photovoltaic materials are muti-aryl compounds. However, the rapid development of transition metal-catalyzed coupling reaction provided us a new breakthrough. In this thesis, the status of organic photoelectric materials research and development background organometallic chemistry were firstly reviewed. The different initiation mode, reaction mode and quenehin mode of C-Pd bond in palladium-catalyzed cross-coupling reactions and the application of tandem reaction in transition metal catalyzed reactions were then surveyed in details. The thesis was focused on the synthesis of the important structure units, fluorene and indenone, in the organic photoelectric materials. The detailed contents are as follows:1. It successfully achieved in simple and readily available substrates, o-bromobenzyl bromide and aryl boronic acid used as the reactants, Pd(OAc)2 as pre-catalyst, PCy3 acted as ligand. In this reaction, it can synthesis of various substituted fluorene derivative in one step smoothly. The biggest advantage was that the reaction in one pot can be formed two new C-C bonds simultaneously and simplified the structure of raw materials to make the reaction more economical and practical at the same time. Moreover, the functional group compatibility of this reaction was relatively good. In addition, we proposed the reaction mechanism through the formation of 2-fluorofluorene which showed that the aromatic C-Br bond coupled with the C-B bond faster than benzyl C-Br bond in this case by analysis of 13 C NMR spectra of the fluorine-substituted fluorene.2. Based on the cross coupling of o-bromobenzyl bromide and aryl boronic acid, we used o-chlorobenzyl bromide instead of o-bromo-benzyl bromide to reduce the reactive of aryl C-X bond, forcing benzyl C-Br bond and Pd(II) to occur oxidative addition reaction, then cross-coupling with aryl boronic acid to achieve the purpose of regulating fluorene derivatives of substituent position. Study found that in the presence of Pd(OAc)2 and PCy3-HBF4, the reaction can also be carried out smoothly. At the same time, through the analysis of 13 C NMR spectra of the fluorine-substituted fluorine showed that the process of the reaction was consistent with we envisaged. We used the same aryl boronic acid and obtained different position of the substituents can be different substituted fluorenes. This work first reported the synthesis of 3-position substituted fluorene.3. The first palladium catalyzed carbonlative for constructing indenone building blocks by tandem reaction was described. Using aryl halides and alkyne as substrates, CO as carbon linker and carbonyl source. Indenone compounds can be receviced under CO atmosphere when aryl halides and alkyne were treated in PdCl2 catalyst system in the presence of sodium carbonate/ TBAB. This reaction could be reacted smoothly under the simple reaction conditions, without any ligand, and good functional group compatibility, a variety of different ortho-halogenated substrates and different internal alkyne could be compatible in this reaction and the yield was relatively good. At the same time, this is the first reported palladium catalyzed carbonylation reaction for constructing indenone compounds. In addition to complete the study of the reaction method, we hypothesized that this reaction was likely to experience a nano palladium catalyzed process and also initially confirmed it by Hg poisoning and ligand poisoning experiments.