2,3-Dihydrofuran Explained

2,3-Dihydrofuran is a heterocyclic compound with the formula . It is isomeric with 2,5-dihydrofuran. 2,3-Dihydrofuran is one of the simplest enol ethers. It is a colorless volatile liquid.

Reactions

It undergoes lithiation upon treatment with butyl lithium. The resulting 2-lithio derivative is a versatile intermediate.^{[1] [2]}

Synthesis and occurrence

2,3-Dihydrofurans are intermediates in the Feist–Benary synthesis of furans from α-halogen ketones and β-dicarbonyl compounds.^[3]

The 2,3-dihydrofuran ring can be synthesized by several methods. These routes usually involve cyclization or cycloaddition reactions of carbonyl compounds using metal-containing catalysts.^{[4] [5]} Iodine can also serve as a catalyst^[6] as well as Raney nickel.^[7]

Notes and References

1. 1,2-Metallate Rearrangement: (Z)-4-(2-Propenyl)-3-octen-1-ol. Krzysztof Jarowicki . Philip J. Kocienski . Liu Qun. Org. Synth.. 2002. 79. 11. 10.15227/orgsyn.079.0011.
2. 10.15227/orgsyn.073.0215 . 4-Ketoundecanoic Acid . Organic Syntheses . 1996 . 73 . 215. M. A. . Tschantz. L. E. . Burgess. A. I.. Meyers .
3. Book: Gilchrist . Thomas L. . Heterocyclic Chemistry . 1997 . Longman . Liverpool . 209–212 . 3rd.
4. An Oxyboration Route to a Single Regioisomer of Borylated Dihydrofurans and Isochromenes. Kim N. Tu . Chao Gao . Suzanne A. Blum. J. Org. Chem.. 2018. 83. 11204. 10.1021/acs.joc.8b01790.
5. Pd-Catalyzed Asymmetric Allylic Substitution Cascade of But-2-ene-1,4-diyl Dimethyl Dicarbonate for the Synthesis of Chiral 2,3-Dihydrofurans. Hao Liu . Zhenliang Sun . Kai Xu . Yan Zheng . Delong Liu . Wanbin Zhang. Org. Lett.. 2020. 22. 4680. 10.1021/acs.orglett.0c01483.
6. Iodine-Catalyzed Synthesis of Substituted Furans and Pyrans: Reaction Scope and Mechanistic Insights. Domenic P. Pace . Raphaël Robidas . Uyen P. N. Tran . Claude Y. Legault . Thanh Vinh Nguyen. J. Org. Chem.. 2021. 86. 8154. 10.1021/acs.joc.1c00608.
7. Reductive Denitrogenation of Six-membered Cyclic Nitronates to Densely Substituted Dihydrofurans with Raney® Nickel/AcOH System. Evgeny V. Pospelov . Alexander V. Zhirov . Baglan Kamidolla . Alexey Yu. Sukhorukov. Adv. Synth. Catal.. 2023. 365. 8154. 10.1002/adsc.202300573.