Dimethylformamide → HCID 22601706, compound

Temperature

23 °C

A suspension of 3-bromo-2,5-diiodo-4-methylthiophene (43 g, 100 mmol) in diethyl ether (300 mL) was treated with an etheral solution of 2.5 M butyllithium (40 mL, 100 mmol) during 5 min at −70 to −60° C. After 10 min, the mixture was treated with N,N-dimethylformamide (11 mL, 140 mmol) and the cooling bath was removed. Upon warming to 23° C., the mixture was quenched with 10% aqueous NH4Cl (500 mL) and extracted with ethyl acetate (3×500 mL). The combined extracts were washed with water and brine (500 mL each), dried (MgSO4) and concentrated in vacuo to give the crude product (31 g) as a rust-colored solid which was recrystallized from hot ethyl acetate. Vacuum filtration gave the title compound (25 g, 76%, m.p. 152-53° C.) as rust-colored needles.

1. customthe cooling bath was removed
2. customthe mixture was quenched with 10% aqueous NH4Cl (500 mL)
3. extractionextracted with ethyl acetate (3×500 mL)
4. washThe combined extracts were washed with water and brine (500 mL each)
5. dry with materialdried (MgSO4)
6. concentrationconcentrated in vacuo
7. customto give the crude product (31 g) as a rust-colored solid which
8. customwas recrystallized from hot ethyl acetate
9. filtrationVacuum filtration

ORD record

ord-9b260965e1ae4d66bdca1b972f6923e6

Source dataset

uspto-grants-2004_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06835745B2