A bis(amino)cyclopropenylidene-catalyzed direct method for the synthesis of α,α'-diarylated ketones from aromatic as well as heteroaromatic aldehydes has been developed. This unprecedented organocatalytic protocol offers access to a wide range of α,α'-diarylated ketones in moderate to excellent yields under mild conditions through umpolung of aldehydes followed by 1,6-conjugate addition with para-quinone methides.

A continuous‐flow homogeneous photocatalytic method has been devised for the direct arylation of 2H‐indazoles. This visible‐light‐promoted approach directly accesses a wide range of structurally diverse C3‐arylated scaffolds of biological interest in a fast (1 min), single‐step reaction by using eosin Y as an organophotocatalyst. Furthermore, a microreactor technology is also employed for the fast synthesis of liver X receptor inhibitor drugs with very good yields under metal‐free conditions, whereas the reported methods required multiple steps and much longer reaction times (18–24 h).

The organocatalytic behavior of N-heterocyclic carbenes in the aerobic oxidation of aromatic aldehydes to esters with boronic acids has been explored. This transition metal-free protocol allows access to a wide variety of aromatic esters in good to excellent yields under mild reaction conditions.

A highly chemoselective intermolecular crossed acyloin condensation between aromatic aldehydes and trifluoroacetaldehyde ethyl hemiacetal has been developed under mild reaction conditions using N-heterocyclic carbene as a catalyst. A wide range of aromatic aldehydes bearing electron-withdrawing and -donating substituents underwent a smooth transformation to their corresponding trifluoromethyl containing acyloin derivatives in moderate to good yields.

Continuous pharmaceutical manufacturing receives intense attention as an alternative way to meet flexible market needs with the assurance of higher safety and quality control.

Visible-light-promoted direct arylation of 2H-indazoles using phenyldiazonium salt enabled a single-step and fast synthesis (<1 min) of C3 arylated products in high yields (>65%) in an eosin Y immobilized capillary microreactor.

In the past decade, microreaction technology has been attracted much attention to the scientific community as one of the subareas in chemical synthesis. The microreactor improves the yield with higher selectivity, and also facilitates the reactions by simple, safe, fast, and green approaches. This review gives an overview on our contributions to develop versatile continuous-flow syntheses and process technology by exampling gas-liquid binary phase in modified PDMS microreactors, and process intensification for safe operation of toxic/hazardous chemistry by generating hazardous chemicals to end utilization via various separation techniques in newly devised systems as well as ordinary capillary reactors. Furthermore, it covers process technology for ultrafast organic synthesis such as submillisecond control of short-lived intermediates in a polyimide chip reactor. These works provide outlooks for integrated and automated flow chemistry via one-flow/feed to end concept, i.e., useful in pharmaceutical industry, toward enabling new and innovative chemistry beyond limits of a batch reactor.

A combination of the oxidative N-heterocyclic carbene catalysis and click chemistry has been explored for the direct, one-pot synthesis of 1,2,3-triazole derivatives from aromatic aldehydes. This procedure was found to be very efficient and a variety of 1,2,3-triazole derivatives could be accessed through their corresponding propargyl esters in moderate-to-good yields under mild conditions.