Palladium Membrane‐Installed Microchannel Devices for Instantaneous Suzuki–Miyaura Cross‐Coupling

Abstract

Instantaneous catalytic carbon-carbon bond-forming reactions were achieved in catalytic membrane-installed microchannel devices that have a polymeric palladium-complex membrane. The catalytic membrane-installed microchannel devices were provided inside the microchannels by means of coordinative and ionic molecular convolution at the interface between the organic and aqueous phases flowing laminarly, in which both non-crosslinked linear polymer ligands and palladium species dissolved. The palladium-catalyzed Suzuki-Miyaura reaction of aryl, heteroaryl, and alkenyl halides with arylboronic acids and sodium tetraarylborates was performed with the catalytic membrane-installed microchannel devices to give quantitative yields of biaryls, heterobiaryls, and aryl alkenes within 5 s of residence time in the defined channel region. These microchannel devices were applied to the instantaneous allylic arylation reaction of allylic esters with arylboron reagents under microflow conditions to afford the corresponding coupling products within 1 s of residence time.

High catalytic efficiency of palladium nanoparticles immobilized in a polymer membrane containing poly(ionic liquid) in Suzuki–Miyaura cross-coupling reaction

“…In our case, poly(ionic liquid) (polyIL) was chemically grafted to micro-PES s support membrane to stabilize palladium nanoparticles by electrosteric effect so that leaching of both nanoparticles and ionic liquid could be effectively prevented. The well-defined palladium nanoparticles immobilized inside the membrane provided catalytically active sites for the organic transformations envisaged [17].…”

A Palladium‐Nanoparticle and Silicon‐Nanowire‐Array Hybrid: A Platform for Catalytic Heterogeneous Reactions

“…[1] One approach is to downsize the reaction field/ space from macroscopic to microscopic scale (e.g., from flask size to microreactor size) to achieve high reactivity and novel selectivity with safety. [2,3] Another is to develop a closed porous space, such as mesoporous silica materials or metalorganic frameworks (MOFs), in which heterogeneous catalysts are attached. [4] While acknowledging the pioneering work in this area, we believe that it remains difficult to create a novel nanospace/field-mediated catalytic transformation system exhibiting high catalytic activity, reusability, safety, and selectivity as well as macroscopic accessibility of a large amount of substrates and reactants under mild and aqueous conditions.…”

A Green Approach to Ethyl Acetate: Quantitative Conversion of Ethanol through Direct Dehydrogenation in a Pd–Ag Membrane Reactor

“…Therefore, if the generated H 2 can be selectively separated in situ from the reaction mixtures, one will be able to drive the reaction to completion. In this regard, supported Pd‐based composite membranes are the most applicable candidates for selective hydrogen removal owing to their high and exclusive hydrogen permeability, high thermal stability, moderate chemical resistance, and mechanical strength 10–15. Such a membrane‐reactor concept has been explored previously for ethanol dehydrogenation with limited success 13.…”