Research on Carbazole Synthesis Lands Cover on Major Scientific Journal
The cover of the December 15, 2023 issue of The Journal of Organic Chemistry published by the American Chemical Society features a chemical formula set against the backdrop of Wulai Falls. The image was selected by Professor of Physical Organic Chemistry Ching-Fa Yao and his Indian postdoctoral fellow Sundaram Suresh. This is Professor Yao’s sixth cover article on an international chemistry journal.
The research highlighted in this publication, “Iodine-Catalyzed Regioselective Synthesis of Diphenyl-Substituted Carbazoles via [4 + 2] Annulation of β-Formyl Ketones with Indoles” (https://pubs.acs.org/doi/10.1021/acs.joc.3c01857), was conducted by postdoctoral researcher Sundaram Suresh and a team of graduate students under the guidance of Professor Ching-Fa Yao. The experimental chemical formula, depicted on the journal cover, metaphorically flows like water over stones, representing the iodine-catalyzed reaction that yields fascinating products.
Renowned international academic journals frequently invite authors to compete for the cover image, and will select one that aligns best with the issue’s theme. Whenever he is invited to contribute such an image to accompany his research, Professor Yao takes great care in selecting Taiwanese landscapes that resonate with the research theme. “In this image, large rocks represent the catalyst iodine used in this experiment. They facilitate the reaction with indole to produce significant outcomes,” Professor Yao explained. “For a previous cover article (September 2023), we chose Hualien’s Chihsing Tan Beach to symbolize the rigorous refinement required to achieve our research outcomes,” he said. “Being selected for a sixth time not only represents recognition for our research but also the journal’s approval of our cover image.”
The carbazole and derivatives produced in the highlighted research are vital nitrogen-containing aromatic heterocyclic compounds known for their strong electron transfer capabilities. These compounds have garnered extensive interest for their applications in optoelectronics, medicine, and materials chemistry due to their molecular conjugation system. Professor Yao’s choices of environmentally-friendly iodine as a catalyst not only aligns with environmental sustainability, but also produces a 80 percent yield, laying a foundation for future advancements.
While there are multiple synthesis methods for carbazole, Professor Yao’s research has identified an ideal condition for synthesis that is both efficient and environmentally-friendly.
“Production costs can escalate in a factory that demands operation under extreme temperatures or complex procedures. This study presents a method that allows reactions to be conducted at mild room temperatures (25°C), utilizing inexpensive and readily available raw materials to achieve high yields,” The reduction in production time and costs gives the method a competitive edge in commercial applications.
Renowned for his extensive research on iodine, Professor Yao’s work is often cited by the global scientific community, and has been recognized by international research institutions. His recent findings provide an efficient, cost-effective alternative for the production of carbazole without the reliance on often toxic transition metals for catalysis. The environmentally friendly option of using iodine molecules already present in the environment will help toward the achieving a greener chemistry.
Professor Yao emphasizes the importance of attention to detail in the laboratory. “I often remind my students not to overlook the details in experimental work. The unexpected often leads to the most amazing outcomes and to beautiful mistakes.” Professor Yao believes that focusing only on prescribed instructions may cause students to miss out on unforeseen phenomena that could prove valuable to research.
In addition to his achievements in chemical research, Professor Yao also serves as a convener for the natural sciences for national and preschool education under the auspices of the K-12 Education Administration (K12EA) at the Ministry of Education. He often travels with other science professors and teachers to schools in rural regions of Taiwan, ensuring that students in these areas are exposed to the wonders of natural science.
Professor Yao’s assistant Hsin-Lun Han describes him as an approachable educator. “Each year, Professor Yao trains a group of university students to support science education in rural areas. Last year alone, they served over 50 primary and secondary school students. He has a strong rapport with his students, and parents are enthusiastic about sending their children to science activities organized by the K12EA and NTNU.”
Over the course of his three decades at NTNU, Professor Ching-Fa Yao has published over 170 papers in international chemistry journals, and registered 10 patents. The majority of his work has been in collaboration with his students, highlighting his commitment to equitable resource distribution and his dual legacy as a distinguished scholar and dedicated educator.