Chemists create eco-friendly method to make chlorine-based materials for drugs and chemicals

A research team led by Julian West, assistant professor of chemistry and Cancer Prevention and Research Institute of Texas (CPRIT) scholar, developed a photocatalytic process that utilizes iron and sulfur catalysts activated by weak blue light Chlorine atoms are added to organic molecules. This innovation eliminates the need for harsh chemicals or high temperatures typically required in the chlorination process, which can create by-products that are difficult to purify.

“Our method uses sustainable, low-cost catalysts and operates at room temperature with soft blue light,” West said. “It provides a targeted, efficient way to chlorinate molecules without the environmental and purification challenges of traditional methods.”

One advantage of the team’s approach is its ability to pinpoint chlorine on the molecule, a process called anti-Markovnikov hydrochlorination. This precision produces high-purity products by selectively attaching chlorine atoms to less reactive parts of the starting molecule. With this approach, chemists can avoid additional purification steps that are often time-consuming and expensive.

The researchers also introduced a new addition to the process: using heavy water to incorporate deuterium, a stable hydrogen isotope. This step can extend the time certain drugs last in the body by making them more stable, potentially increasing their effectiveness.

“What’s exciting is that this approach could open new doors for modifying drugs and natural products that were not possible with older technologies,” West said.

Research collaborators include Rice students Kang-Jie Bian, Shih-Chieh Kao, Ying Chen, Yen-Chu Lu, David Nemoto Jr. and Xiaowei Chen.

Angel Marti, professor and department chair of chemistry and professor of bioengineering, materials science and nanoengineering, also contributed to the research, which was supported by CPRIT, the Welch Foundation, the Science Advances Research Corporation and the American Chemical Society Petroleum Research Fund support.