Preparation And Catalytic Properties For Suzuki Reaction Under Microwave Of PVDC Supported Catalysts

Carbon-carbon bond formation reactions are some of the most important processes in chemistry,which provide key steps in the building of more complex molecules from simple precursors.The palladium-catalyzed cross-coupling reaction represents one of the most straightforward method for carbon-carbon bond formation.Among palladium-catalyzed cross-coupling processes,the Suzuki reaction of aryl and vinyl halides or triflates with organoboron compounds provides a powerful and general methodology,which is emerging as a favorite.A brief introduction is given in Chapter 1 with an emphasis on the background information closely related to the topics of this thesis。we wish to present in this report some of the recent advances involving non-conventional methodologies that have been applied to the Suzuki reaction.We present in Chapter 2 a series family of air-stable supporters for palladium-catalyzed Suzuki coupling reaction of iodobenzene and tetraphenylboron sodium.The catalytic property of polyvinylidene chloride polyethylene polyamine palladium complex (PVDC-DETA-Pd,PVDC-TETA-Pd,PVDC-TEPA-Pd)for Suzuki reaction of sodium tetraphenylborate with iodobenzene were examined under microwave heating.The results showed that under 200W power,in the present of various alkalis,e.g. NaHC0₃,NaOAc,Na₂CO₃,and DMF-H₂O(V:V=4:3)used as solvent,those series of catalysts could catalyze sodium tetraphenyborate to react quantificationally with iodobenzene in 20 min without inserting gas protection,with conventional heating,microwave heating could save much time.After being recycled and reused more than four times,the catalyst had still high catalytic activity.In Chapter 3,we get an excellent result when we use PEG instead of DMF as solvent for Suzuki reaction.But when PEG as solvent the seried of catalysts have a poor recycled property.Chapter 4 focuses on development of a microwave-based high-throughput protocol for optimization of new supporter with improved catalytic efficiency.Polyvinylidene chloride-diphenylamin was synthesized from polyvinylidene chloride via animation, then polyvinylidene chloride-diphenylamine supported palladium complex (PVDC-DPA-Pd)was prepared and characterized by IR,TG,DTA,etc. PVDC-DPA-Pd has good thermal stability from room temperature to 150℃.The complex is an efficient catalyst for Suzuki coupling reaction of sodium tetraphenylborate with aryl bromides under atmospheric condition,even at the short time(10 min).Yield of biphenyl was 75%for Suzuki reaction of sodium tetraphenylborate with bromoarene even though the complex was used 3 times.