Design Of The Numbering-up Reactors To Effectively Improve The Catalytic Efficiency And Its Application In Suzuki-Miyaura Reactionon

By the time Suzuki was awarded the Nobel prize in Chemistry in 2010,the main obstacles of the Suzuki-Miyaura reaction concerning challenging substrates had been solved,the research was somewhat reoriented to upgrade the efficiency of the catalytic systems ever since.In this work,a novel numbering-up reactor was set up with the self-supporting palladium catalyst?P?b-NHC-Pd??for a continuous flow process in Suzuki-Miyaura reaction.The responding results of this work are listed as follows:?1?Flow chemistry has been proposed in modern organic chemistry as a mean for process intensification,to improve the control over reaction performance and to achieve higher yield.owing to microreactor technology small sizes and the resulting high surface area-to-volume ratios,microreactors offer great advantages over conventional batch reactors,such as higher mixing efficiency,enhanced mass and heat transfer rates,precise control over reaction conditions,and improved process safety.we figure out the best ways to combine and arrange a single micro-reactor with its counterparts catalysts.A series of numbering-up reactors were designed in this work to perform this Suzuki-Miyaura reaction.The catalytic efficiency was improved more than 5.3 times at the same amount of the catalyst only depending on the design of the numbering-up reactors.?2?Based on the requirements of the reactor for catalyst effective separation,high throughput and low pressure drop.We designed the synthetic route of the self-supporting catalyst and explored a simple and effective synthetic scheme for the preparation of N-heterocyclic carbene polymer.To elucidate the reaction mechanism of the present transformations.Especially,for the continuous flow reactor,this self-supporting catalyst might be the key to overcome the problems of the low throughput,tendency to channel blockage and high pressure drop.Detailed analysis was performed to investigate the proportion of the effect of 2,6-diisopropylaniline and formaldehyde The average molecular weight?????of synthesized poly?diamine?was mediated by the change reaction time,pH and removing the side products.The highest average molecular weight?????of synthesized poly?diamine?reaches 25382 g/mol and its polymerization degree?????is about 55.The performance of the catalyst improves as a function of the catalyst molecular weight.Tg of the catalyst is increased from 138.5?to 147.5?with the increasing of its average molecular weight.It's responding particles size gradually increases from 2.56?m to 25.01?m.?3?Catalyst exhibits good catalytic activity and substrate suitability for Suzuki-Miyaura reaction of aryl bromides and aryl chlorides,the palladium content of this catalyst even reaches 1.8 mmol/g.When 0.1 mol%of P?b-NHC-Pd?was used,the conversion of this Suzuki-Miyaura reaction changed little after 10 runs.When the reaciton was catalyze by tetrakis?triphenylphosphine?palladium,the activation energy??E?was about 14.74 KJ/mol.The activation energy decreased to 9.22 KJ/mol as P?b-NHC-Pd?performed as the catalyst.The parameter(k_app/nPd)of P?b-NHC-Pd?is always higher than that of tetrakis?triphenylphosphine?palladium in different temperature,which means the catalytic activity of P?b-NHC-Pd?is higher than that of tetrakis?triphenylphosphine?palladium.