Toluene → 3-Bromo-4-(4-methoxyphenyl)thiophene

HRID 536603Notes

Reaction equation

Br[C:2]1[C:6]([Br:7])=[CH:5][S:4][CH:3]=1.[CH3:8][O:9][C:10]1[CH:15]=[CH:14][C:13](B(O)O)=[CH:12][CH:11]=1.C(=O)([O-])[O-].[Na+].[Na+].C1(C)C=CC=CC=1>C(O)C.O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[Br:7][C:6]1[C:2]([C:13]2[CH:14]=[CH:15][C:10]([O:9][CH3:8])=[CH:11][CH:12]=2)=[CH:3][S:4][CH:5]=1

Participants

Conditions

Temperature: 75 °C

Procedure

To a mixture of 3,4-dibromothiophene (Scheme I, 1) (5 g, 20.7 mmol), 4-methoxyphenylboronic acid (Scheme I, 2, X1=4-methoxyphenyl) (3.14 g, 20.7 mmol), sodium carbonate (4.38 g, 41.3 mmol), toluene (100 mL), in a mixture of ethanol (60 mL) and water (40 mL) was added Pd(PPh3)4 (2.02 g, 1.75 mmol) under nitrogen. The mixture was stirred at 75° C. for 13 h, poured into water (60 mL), and extracted with ethyl acetate (60 mL×3). The organic extracts were dried over anhydrous magnesium sulfate (10 g), evaporated, and purified by column chromatography on silica gel (petroleum ether/ethyl acetate=150:1) to give 3-bromo-4-(4-methoxyphenyl)thiophene (Scheme I, 2, X1=4-methoxyphenyl) (1.7 g, yield 30.6%). 1H NMR (DMSO-d6 400 MHz): δ 7.84 (d, J=3.2 Hz, 1H), 7.64 (d, J=3.2 Hz, 1H), 7.42 (d, J=8.8 Hz, 2H), 6.97 (d, J=8.8 Hz, 2H), 3.78 (s, 3H).

Workup

extractionextracted with ethyl acetate (60 mL×3)
dry with materialThe organic extracts were dried over anhydrous magnesium sulfate (10 g)
customevaporated
custompurified by column chromatography on silica gel (petroleum ether/ethyl acetate=150:1)

Sources & evidence

ORD record: ord-ca4a419e7b6c48ccaae136d7f43e851b
Source dataset: uspto-grants-2014_10
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08859611B2

Reaction notes

Loading…