2-Bromo-3-methylthiophene → 2-(2-Methoxy-ethyl)-3-methyl-thiophene

A part of a solution containing 2-bromo-3-methylthiophene CAS14282-76-9 (1.5 g, 8.5 mmol) in dry diethyl ether was added drop-wise to a suspension of magnesium (308 mg, 12.7 mmol, 1.5 equiv.) in dry diethyl ether, until the mixture started to reflux. The remaining solution was added dropwise. A solution of toluene-4-sulfonic acid 2-methoxy-ethyl ester (2.9 g, 12.7 mmol, 1.5 equiv.) in dry diethyl ether was added dropwise at room temp., then the mixture was refluxed for two hours. After cooling down to room temp., the mixture was quenched with ammonium chloride solution saturated and extracted with tert. butylmethyl ether. The combined organic extracts were washed with water and brine, dried over magnesiumsulfate-dihydrate and purified on silica gel with eluent n-heptane and tert.butylmethyl ether. The title compound was obtained as light yellow oil: 490 mg, GC-MS (EI) M=156.

1. temperatureto reflux
2. additionThe remaining solution was added dropwise
3. temperaturethe mixture was refluxed for two hours
4. temperatureAfter cooling down to room temp.
5. customthe mixture was quenched with ammonium chloride solution saturated
6. extractionextracted with tert. butylmethyl ether
7. washThe combined organic extracts were washed with water and brine
8. dry with materialdried over magnesiumsulfate-dihydrate
9. custompurified on silica gel with eluent n-heptane and tert.butylmethyl ether

ORD record

ord-94455c993f8841428b257b3430f0d43c

Source dataset

uspto-grants-2011_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07964633B2