Pyridine → 1-Nitrodibenzofuran

In a flame dried 3-neck flask, CuI (10.3 g, 54.3 mmol) and tBuOK (6.7 g, 60 mmol) were stirred in 120 mL dimethoxyethane for 1 h. To the stirred solution was added 280 mL pyridine and the solution turn purplish. In a separate flask 2-iodophenol (24.1 g, 109 mmol) and tBuOK (12.9 g, 115 mmol) were dissolved in 60 mL dimethoxyethane and transferred to the reaction flask. Solid 2,4-dinitrodibenzofuran (16 g, 95 mmol) was then immediately added to the reaction flask and stirred for 10 minutes. Reaction mixture was then refluxed for 2.5 h. After completion, reaction mixture was cooled and carefully quenched with 8M H2SO4. Dark color solution was filtered thru a Celite and the filtrate was partitioned between ethylacetate and water. Aqueous layer was extracted twice with ethylacetate. Combined organic layer was washed with sodium sulfite solution followed by Na2CO3 solution and dried over anhydrous Na2SO4. Organic solvent was removed under vacuum. Crude product was purified by flash chromatography over silica gel with 20% DCM/Hexanes. Target compound (13 g, 64% yield) was isolated as yellow solid upon evaporation of organic solvent under vacuum.

1. customIn a flame dried 3-neck flask
2. customReaction mixture
3. temperaturewas then refluxed for 2.5 h
4. customAfter completion, reaction mixture
5. temperaturewas cooled
6. customcarefully quenched with 8M H2SO4
7. filtrationDark color solution was filtered
8. customthe filtrate was partitioned between ethylacetate and water
9. extractionAqueous layer was extracted twice with ethylacetate
10. washCombined organic layer was washed with sodium sulfite solution
11. dry with materialdried over anhydrous Na2SO4
12. customOrganic solvent was removed under vacuum
13. customCrude product was purified by flash chromatography over silica gel with 20% DCM/Hexanes

ORD record

ord-493575fb91a14ba7ae2f522fcf28e865

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09156870B2