2024/04/18
Keio University
Associate Professor Takuya Kawachi, Associate Professor Miho Hatanaka, and their colleagues at the Department of Chemistry, Faculty of Science and Technology, Keio University, have discovered that the most difficult step in an organic reaction can be a rotational process, which was conventionally considered easy, rather than the process of bond rearrangement, which was previously thought to be the most difficult.
Organic compounds play a wide and important role in daily life. They are synthesized by repeatedly forming and breaking bonds through various organic reactions, with bond formation and cleavage being key processes for creating new molecules. Each organic reaction proceeds through multiple stages; some involve the formation or cleavage of bonds, while others only involve bond rotation. In organic reactions, the bond formation and cleavage processes are generally considered the most crucial. However, this study, through verification using computational simulations known as DFT calculations and experiments, has successfully demonstrated that the most difficult step in an organic reaction involving bond formation and cleavage can be a process that does not involve either. For the reaction investigated, DFT calculations revealed that while bond formation and cleavage occur repeatedly, the process that most hinders its progress is bond rotation—a step conventionally considered easy. Furthermore, the difficulty of this rotation suggested that the reaction proceeds via a mechanism different from the established theory, a finding supported by experimental results. This research shows that combining computational simulations with experimental verification can deepen the fundamental understanding of organic chemistry in areas previously considered challenging, and it is expected to contribute to the further advancement of the field.
The results of this research were published online in The Journal of Organic Chemistry (published by the American Chemical Society) on March 25, 2024 (local time). The work was also selected to be featured on the journal's supplementary cover.
For the full press release, please see below.