N-methyl-2-pyrrolidone → 2-Chloro-4-methylthieno[3,4-B]pyridine

A solution (0.67 mL) of 3 M methyl magnesium chloride in THF was added dropwise to a mixture of 2,4-dichlorothieno[3,4-b]pyridine (0.37 g), iron(III) acetylacetonate (0.064 g), N-methyl-2-pyrrolidinone (1 mL), and THF (15 mL) with ice cooling, and the mixture was stirred at room temperature for 20 h. The reaction solution was diluted with water, and the mixture was extracted with chloroform. The organic layer was dried with anhydrous magnesium sulfate, then the desiccant was removed by filtration, and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (silica gel and NH silica gel, ethyl acetate/hexane=20:1-10:1) to obtain 2-chloro-4-methylthieno[3,4-b]pyridine (0.027 g).

1. extractionthe mixture was extracted with chloroform
2. dry with materialThe organic layer was dried with anhydrous magnesium sulfate
3. customthe desiccant was removed by filtration
4. concentrationthe filtrate was concentrated under reduced pressure
5. customThe residue was purified by silica gel column chromatography (silica gel and NH silica gel, ethyl acetate/hexane=20:1-10:1)

ORD record

ord-996ced264547429288af5a27277219e5

Source dataset

uspto-grants-2011_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08044068B2