Flash Generation of a Highly Reactive Pd Catalyst for Suzuki-Miyaura Coupling by Using a Flow Microreactor

Flash Organometallic Catalysis Uncovered by Continuous Microfluidic Devices

The flash organometallic catalysis is a new concept that refers to the study of fast and controlled organometallic catalytic reactions by using microfluidic devices. Flash reactions' kinetics (ms-s scale) is often ignored due to the lack of proper research tool in organometallic chemistry. The development of microfluidic systems offers the opportunity to discover under-studied mechanisms and new reactions. In this concept, the basic theory of kinetic measurement in a microreactor is briefly reviewed and then two examples on studying flash organometallic catalytic transformation are introduced. One example is the discovery of a highly active palladium catalytic species for Suzuki Coupling and the other example is the study of a neglected isomerization catalytic cycle with a time scale of seconds before isomerization-hydroformylation by customized microfluidic devices. The last part is summary and prospect of this new area. Customizing a microfluidic device with good engineering design for a target reaction supports flash reactions' kinetic experimentation and could become a general strategy in chemistry lab.

Process Intensification of a Napabucasin Manufacturing Method Utilizing Microflow Chemistry

Microflow chemistry is one of the newest and most efficient technologies used today for the safe and effective production of medicines. In this paper, we show the use of this technology in the development of a manufacturing method for napabucasin, which has potential in the treatment of colorectal and pancreatic cancers. In conventional "batch-type" reactor systems, the generation of side products can be controlled with traditional techniques such as reagent reverse-addition and temperature control. However, there is a limitation to which the yield and purity can be improved by these methods, as both are constrained by the efficiency of heat/mass transfer. Applying microflow chemistry technology alters the parameters of the constraint through the use of precise mixing in a microchannel, which offers increased possibility for improving yields and process intensification of the napabucasin process. Reported herein is a proof-of-concept study for the scale-up production of napabucasin using microflow chemistry techniques for manufacturing at the kilogram scale.

One-Pot Synthesis of Multiarylated Benzophenones via [3 + 2 + 1] Benzannulation of Ketones, Alkynes, and α,β-Unsaturated Carbonyls

In this study, we synthesized γ-phenyl-β,γ-unsaturated ketones in situ from acetophenones and phenylacetylenes under Trofimov's conditions using KOtBu in a dimethyl sulfoxide (DMSO) solvent. The obtained ketones reacted with α,β-unsaturated carbonyls in a one-pot manner, forming tri- or diarylated benzophenones. The present reaction proceeded efficiently by one-pot manipulation with a suitable carboxylic acid.

Synthesis and biological evaluation of 3,5-substituted pyrazoles as possible antibacterial agents

The emergence of multi-drug resistant bacteria has increased the need for novel antibiotics to help overcome what may be considered the greatest threat to modern medicine. Here we report the synthesis of fifteen novel 3,5-diaryl-1H- pyrazoles obtained via one-pot cyclic oxidation of a chalcone and hydrazine-monohydrate. The synthesised pyrazoles were then screened against Staphylococcus aureus and Escherichia coli to determine their antibacterial potential. The results show that compound 7p is bacteriostatic at MIC 8 µg/mL. The compound is non-toxic against healthy mammalian cells, 3T3-L1 at the highest test concentration 50 µg/mL. Furthermore, compound 7p significantly affected bacterial morphogenesis before cell lysis in Bacillus subtilis when treated above the MIC concentration. From the results, a promising lead compound was identified for future development.

Homogeneous Catalyzed Aryl–Aryl Cross-Couplings in Flow

Aryl–aryl cross-coupling reactions are important reactions for the production of various biaryl compounds. This short review covers the various aryl–aryl cross-coupling reactions carried out in flow, focusing on the metal species of the aryl nucleophiles used in the cross-coupling reactions.

1 Introduction

2 Suzuki–Miyaura Coupling (B)

3 Migita–Kosugi–Stille Coupling (Sn)

4 Negishi Coupling (Zn)

5 Kumada–Tamao–Corriu Coupling (Mg)

6 Murahashi Coupling (Li)

7 Conclusion

Space and time-resolved probing of heterogeneous catalysis reactions using lab-on-a-chip

Probing catalytic reactions on a catalyst surface in real time is a major challenge. Herein, we demonstrate the utility of a continuous flow millifluidic chip reactor coated with a nanostructured gold catalyst as an effective platform for in situ investigation of the kinetics of catalytic reactions by taking 5-(hydroxymethyl)furfural (HMF) to 2,5-furandicarboxylic acid (FDCA) conversion as a model reaction. The idea conceptualized in this paper can not only dramatically change the ability to probe the time-resolved kinetics of heterogeneous catalysis reactions but also used for investigating other chemical and biological catalytic processes, thereby making this a broad platform for probing reactions as they occur within continuous flow reactors.

Flash chemistry: flow chemistry that cannot be done in batch

Flash chemistry based on high-resolution reaction time control using flow microreactors enables chemical reactions that cannot be done in batch and serves as a powerful tool for laboratory synthesis of organic compounds and for production in chemical and pharmaceutical industries.