2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → HCID 57428834, compound

Temperature

-78 °C

nBuLi (1.1 mL, 1.6 M solution in hexane, 1.8 mmol) was added to a stirred solution of 2,3-dibromo-5-chlorothiophene (0.50 g, 1.8 mmol) in 10 mL of THF at −78° C. The solution was stirred for 10 min at −78° C. before 0.35 g (1.8 mmol) of 5-bromo-2-chloropyrimidine was added. The reaction solution was stirred for 30 min at −78° C., then quenched by addition of 1 mL of AcOH in 4 mL of MeOH. Solid 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (0.82 g, 3.6 mmol) was added and the reaction mixture warmed to 0° C. and stirred for 10 min. The reaction mixture was then poured into 50 mL of a 0.5 M solution of sodium ascorbate and diluted with 100 mL of a 1 M aqueous solution of Na2CO3. The aqueous solution was extracted four times with CH2Cl2 and the combined organic extracts dried over MgSO4, filtered and concentrated to give the crude product which was purified by flash chromatography eluting with a linear gradient of 50% EtOAc in hexane to neat EtOAc, then to 20% MeOH in EtOAc to deliver the title compound. MS (M+H)+ 389.

1. additionwas added
2. customquenched by addition of 1 mL of AcOH in 4 mL of MeOH
3. temperaturethe reaction mixture warmed to 0° C.
4. stirringstirred for 10 min
5. extractionThe aqueous solution was extracted four times with CH2Cl2
6. dry with materialthe combined organic extracts dried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated

ORD record

ord-2180869d03084fa6a95efc6cee2889cc

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07786132B2