Li, X., Yongcai, W., Lijuan, S., & Zhang, Y. (2022). Catalytic Halogen‐Exchange Fluorination of 4‐Chlorobenzaldehyde to 4‐Fluorobenzaldehyde, a Greener Process. Asian Journal of Organic Chemistry, 11(2). Portico. https://doi.org/10.1002/ajoc.202100732
The direct halogen-exchange fluorination of 4-chlorobenzaldehyde was studied under solvent-free and various diphenyl solvents conditions using spray-dried KF as a fluorinating agent. Aspects influencing the selectivity and yield of product were investigated in detail, including catalysts and solvents selection, reaction conditions optimization, and side product control. We paid more attention to issues from a perspective of industrial process, such as product separation and catalyst/solvent recycling. The reaction works efficiently with tetraphenyl phosphonium bromide as a phase transfer catalyst under solvent free conditions and in diphenyl solvents. Under the optimum reaction conditions, the yield of 4-fluorobenzaldehyde reached 90% with a selectivity of 98%.
This research is supported by core funding from: A*STAR, Institute for Bioengineering and Bioimaging (IBB)
Grant Reference no. : SC19/17-300412
This is the peer reviewed version of the following article: Li, X., Yongcai, W., Lijuan, S., & Zhang, Y. (2022). Catalytic Halogen‐Exchange Fluorination of 4‐Chlorobenzaldehyde to 4‐Fluorobenzaldehyde, a Greener Process. Asian Journal of Organic Chemistry, 11(2). Portico. https://doi.org/10.1002/ajoc.202100732, which has been published in final form at doi.org/10.1002/ajoc.202100732. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited