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Review
. 2023 Jan 14;27(2):262-268.
doi: 10.1021/acs.oprd.2c00222. eCollection 2023 Feb 17.

Continuous Flow Epoxidation of Alkenes Using a Homogeneous Manganese Catalyst with Peracetic Acid

Ailbhe A Ryan  1   2   3 , Seán D Dempsey  1   2   3 , Megan Smyth  1 , Karen Fahey  2 , Thomas S Moody  1   2 , Scott Wharry  1 , Paul Dingwall  3 , David W Rooney  3 , Jillian M Thompson  3 , Peter C Knipe  3 , Mark J Muldoon  3
Affiliations
Review

Continuous Flow Epoxidation of Alkenes Using a Homogeneous Manganese Catalyst with Peracetic Acid

Ailbhe A Ryan et al. Org Process Res Dev. .

Abstract

Epoxidation of alkenes is a valuable transformation in the synthesis of fine chemicals. Described herein are the design and development of a continuous flow process for carrying out the epoxidation of alkenes with a homogeneous manganese catalyst at metal loadings as low as 0.05 mol%. In this process, peracetic acid is generated in situ and telescoped directly into the epoxidation reaction, thus reducing the risks associated with its handling and storage, which often limit its use at scale. This flow process lessens the safety hazards associated with both the exothermicity of this epoxidation reaction and the use of the highly reactive peracetic acid. Controlling the speciation of manganese/2-picolinic acid mixtures by varying the ligand:manganese ratio was key to the success of the reaction. This continuous flow process offers an inexpensive, sustainable, and scalable route to epoxides.

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Conflict of interest statement

The authors declare no competing financial interest.

Figures

Figure 1
Figure 1
Alkene epoxidation using manganese triflate, 2-picolinic acid, and peracetic acid as reported by Stack and co-workers. PAAM = 10:3:13 v/v/v 32 wt% PAA/10 wt% KOH(aq)/AcOH.
Figure 2
Figure 2
Initial setup for flow reactions with Mn(OAc)2.
See this image and copyright information in PMC

References

    1. Lin Z.; Huang B.; Ouyang L.; Zheng L. Synthesis of Cyclic Fragrances via Transformations of Alkenes, Alkynes and Enynes: Strategies and Recent Progress. Molecules 2022, 27 (11), 3576.10.3390/molecules27113576. - DOI - PMC - PubMed
    1. Gomes A. R.; Varela C. L.; Tavares-da-Silva E. J.; Roleira F. M. F. Epoxide Containing Molecules: A Good or a Bad Drug Design Approach. Eur. J. Med. Chem. 2020, 201, 112327.10.1016/j.ejmech.2020.112327. - DOI - PubMed
    1. Delost M. D.; Smith D. T.; Anderson B. J.; Njardarson J. T. From Oxiranes to Oligomers: Architectures of U.S. FDA Approved Pharmaceuticals Containing Oxygen Heterocycles. J. Med. Chem. 2018, 61 (24), 10996–11020. 10.1021/acs.jmedchem.8b00876. - DOI - PubMed
    1. Moschona F.; Savvopoulou I.; Tsitopoulou M.; Tataraki D.; Rassias G. Epoxide Syntheses and Ring-Opening Reactions in Drug Development. Catalysts 2020, 10 (10), 1117.10.3390/catal10101117. - DOI
    1. Thirumalaikumar M. Ring Opening Reactions of Epoxides. A Review. Org. Prep. Proced. Int. 2022, 54 (1), 1–39. 10.1080/00304948.2021.1979357. - DOI