Rapid Synthesis of Novel Drugs Using Fluorine

How short is one second? The duration of a second can be defined as one of the 86400th of a 24-hour day. A high-speed train traveling at 300 kilometers per hour can cover a distance of 83 meters in one second. On average, an individual’s blink lasts 0.3 seconds, allowing for three flashes to occur within one second. A joint team of researchers from POSTECH has proposed a method for synthesizing a fluorine-based compound via a rapid mixing reaction between a gaseous component and a liquid that takes less than one second.

The research team led by Professors Dong-Pyo Kim and Jeong-Un Joo (Department of Chemical Engineering at POSTECH), Professors Heejin Kim and Hyune-Jea Lee (currently, Researcher at Samsung Advanced Institute of Technology) from the Department of Chemistry at Korea University has succeeded in developing a method Novel for the synthesis of trifluoromethyl intermediate (-CF3) from fluoroform (CHF3).

It involves the use of a special reactor capable of achieving ultra-fast mixing of gas and liquid. This method offers promising prospects for the synthesis of new fluorine-based drugs. Research published in Nature Communications.

Fluorine does not exist in its pure form naturally, but only exists in the form of various chemical compounds. Sodium fluoride, a fluorine-containing compound, is used as an ingredient in toothpaste due to its ability to coat teeth and prevent cavities.

Recent studies have highlighted the potential of synthetic fluorine-containing drug molecules because they possess high permeability in the cell membranes of diseased tissues and show strong binding affinity against proteins. Thus, there is a growing interest in developing fluorine-containing medicines.

There are several ways to synthesize trifluoromethyl, but the most cost-effective method involves replacing the hydrogen atom of fluoroform, a simple precursor, with another element or functional group. However, gaseous fluoroform is volatile, which makes it difficult to mix with liquids and shows low reactivity. Moreover, it decomposes instantly, requiring the addition of a substance with which it can interact. Unfortunately, this process can lead to unintended chemical reactions that result in decreased TMF production.

To address the challenge of synthesizing trifluoromethyl from fluoroform, the research team developed a novel gas-liquid reactor with a zigzag-shaped channel and non-porous, high-permeability membranes sandwiched between the top and bottom channels. This configuration allowed the circulating and mixing of the superbase, a liquid used for dehydrogenation, and gaseous fluoroform inside the reactor.

By breaking the fluoroform bubbles into smaller pieces to increase the gas-liquid contact area, the team was able to effectively produce the trifluoromethyl (CF) anion.₃^–). In contrast to traditional methods, they effectively produced a fluoride intermediate without the need for stabilizers or additives.

The research team made a fluorine-based compound by instantly adding a compound that reacted with the intermediate fluoride anion. The entire process, which involved generating an intermediate fluorine anion from fluoroform, was done within a second. The team maximized the formation of the trifluoromethyl anion, which is known to be short-lived, and quickly facilitated the subsequent reaction before the intermediate decomposition.

This method allowed for improved yield of fluoride-based compounds and provided a powerful technology for the synthesis of fluorine-containing drugs.

The results of the research have significant implications for industrial applications in the economically efficient synthesis of fluoride compounds, making them more practical as well as contributing significantly to studies on many unstable media.