Research

Considering Green Chemistry as a keyword, our organic synthesis laboratory are focusing on following topics.

1. Activation of Esters and Amides 

2. Design of Chiral Organocatalysts

3. Development of Organocatalyzed Asymmetric Reactions

Esters and amides are crucial functional groups found in natural products, pharmaceuticals, agrochemicals, and various chemical materials. They also play a significant role in synthetic chemistry. As a result, the efficient transformation and synthesis of esters and amides are highly attractive research topics for organic chemists.  

We are exploring the development of a unique and effective method for activating esters and amides to facilitate various transformations through the cleavage of C–O and C–N bonds under mild and environmentally friendly conditionsAs a representative protocol, we are using hypervalent iodine(III) reagents to activate ester functionality which possesses phenol moiety as a potential activating group. 

Organocatalyst has become a great topic of scientific interest in both academic and industrial laboratories due to environmental friendless, simple operation, mild reaction conditions, and low cost. For example, L-proline, one of the chiral α-amino acid in nature, have been developed as strong bifunctional organocatalyst and employed in various asymmetric transformations. L-proline indeed made a big contribution to development of asymmetric organocatalysis and Benjamin List, who investigated its catalytic effect, won the Nobel Prize in chemistry in 2021. 

We are working on design of bifunctional organocatalyst which is showing high catalytic performance in asymmetric transformations such as aldol reactions and Mannich reactions. To enhance reactivity and stereoselectivity, we are modifying basicity of amine functionality, acidity of acid functionality, rigidity and steric hinderance of backbone, and distance between acid and base functionalities. 

Chirality of organic molecule is important key of bioactivity of natural products, drugs, and agrochemicals. Indeed, about half of the drugs in current market is chiral products and the effect of each enantiomeric drug is completely different. To avoid unexpected side effect, it is clearly important to prepare both enantiomers and check the activity, respectively. Accordingly,  asymmetric catalytic reaction have been highlighted as powerful tool to synthesize chiral target molecules efficiently.

We are developing novel asymmetric catalysis to prepare interesting chiral backbone which can be founded in bioactive compounds. In particular, various stereoselective methodologies for synthesizing N-heterocycles, for example pyrrolizine, pyrrolopiperazinones, azetidines, and isoxazolines, have been developed employing heteroatom nucleophiles in the presence of organocatalyst such as phase-transfer-catalyst and aminocatalyst.