Studies On The Synthesis Of Ferrocenyl Allenes And Palladium-Catalyzed Three-Component Coupling Reactions

Allenes are a group of compounds which are featured by the presence of two cumulative C=C double bonds. They behave a variety of interesting and peculiar reaction performances due to the excellent capacity of the substituent loading for the four sites of its end. In the past decades, the allene chemistry has acquired considerable development. More and more novel reactions based on the allene chemistry have been applied to the synthesis of natural products, pharmaceuticals. dyes. polymers, and so on. On the other hand, as a series of extremely significant organometallic compounds, ferrocene and its derivatives have been extensively used in the fields of asymmetric catalysis, non-linear optical materials, bioorganometallic chemistry, supramolecular chemistry, etc. Besides, the ferrocenvl allene is a sort of chemical which simultaneously possesses ferrocenvl and1,2-dienyl functional groups. Therefore, its synthesis and properties deserve investigation and exploration.The current thesis is mainly constituted by two parts listed as follows:Part â… :We have successfully synthesized ferrocenvl allenes via the Crabbe homologation reaction. In a typical process, the mixture of diisopropylamine, ferrocenylacetylene, and paraformaldehyde in toluene reaction medium was catalyzed by Cul and90%yield of ferrocenvl allene was finally obtained. Moreover, the universality of this reaction was also investigated in this thesis.Part â…¡:We found the reaction of ferrocenyl allene with iodobenzene and methyl phenyldiazoacetate in the presence of Cs2CO3catalyzed by Pd(OAc):in MeCN can afford butadienylferrocene products. This synthesis strategy was outstanding for its simple procedure and high yield. Thus, the present tactic provided an efficient means of the preparation for butadienylferrocenes. The reaction is proposed to involve an interesting allyl migratory insertion of a palladium carbene complex.