Preparation
2,5-Diphenylfuran Synthesis: Using the batch general procedure, commercially available trans,trans-1,4-diphenyl-1,3-butadiene (1) (412 mg, 2.00 mmol) and rose Bengal disodium salt (6 mg, 0.005 mmol) in 19:1 CH?Cl?/MeOH (60 mL) provided the intermediate endoperoxide, 3,6-diphenyl-3,6-dihydro-1,2-dioxine (3), as a colorless solid after column chromatography (308 mg, 1.30 mmol, 65%); R_f = 0.15 (9/1 hexanes/ethyl acetate).
1H NMR (CDCl?, 500 MHz): δ 7.77 (d, 4H, J = 8.0 Hz), 7.43 (t, 4H, J = 7.5 Hz), 7.29 (t, 2H, J = 7.5 Hz), 6.75 (s, 2H).
13C {1H} NMR (CDCl?, 126 MHz): δ 137.7, 128.8, 128.7, 128.5, 127.5, 80.3.
Using the general batch procedure and 3 (120 mg, 0.50 mmol), PPh? (144 mg, 0.55 mmol), and CBr? (182 mg, 0.55 mmol), 2,5-Diphenylfuran was obtained as a colorless solid after column chromatography (112 mg, 0.50 mmol, 99%); R_f = 0.40 (9/1 hexanes/ethyl acetate).
1H NMR (CDCl?, 500 MHz): δ 7.77 (d, 4H, J = 7.3 Hz), 7.43 (t, 4H, J = 7.5 Hz), 7.29 (t, 2H, J = 7.5 Hz), 6.76 (s, 2H).
13C {1H} NMR (CDCl?, 126 MHz): δ 153.4, 130.9, 128.8, 127.4, 123.8, 107.3.
IR (ν_max, cm?1): 2980, 1662, 1600, 1587, 1508, 1479, 1447, 1386.
References
[1] HELENA F. GRANTHAM, MARC C. KIMBER* Transition-Metal-Free Continuous-Flow Synthesis of 2,5-Diaryl Furans: Access to Medicinal Building Blocks and Optoelectronic Materials[J]. The Journal of Organic Chemistry, 2023, 89 1: 484-497. DOI:
10.1021/acs.joc.3c02237.
[2] EBERHARDT M K. Formation of cis-1,2-dibenzoylethylene from 2,5-diphenylfuran by Fenton’s reagent and by peroxydisulfate. Effect of oxygen[J]. The Journal of Organic Chemistry, 1993, 58 2: 497-498. DOI:
10.1021/jo00054a038.
[3] HU SHENG-LI. Synthesis, Crystal Structure and Binding Properties of a New Fluorescent Molecular Clip Based on 2,5-diphenylfuran[J]. Journal of Chemical Research-s, 2013, 1 1: 210-212. DOI:
10.3184/174751913X13626742215922.
[4] DR. LEONID V. ROMASHOV. Atom-economic Approach to the Synthesis of α-(Hetero)aryl-substituted Furan Derivatives from Biomass[J]. Chemistry - An Asian Journal, 2021, 17 1. DOI:
10.1002/asia.202101227.
