Chlorotrimethylsilane → Di-isobutyl thiophene-3,4-dicarboxylate

Reaction equation

[S:1]1[CH:5]=[C:4]([C:6]([OH:8])=[O:7])[C:3]([C:9]([OH:11])=[O:10])=[CH:2]1.Cl[Si](C)(C)C.[CH3:17][CH:18]([CH3:21])[CH2:19]O>>[S:1]1[CH:5]=[C:4]([C:6]([O:8][CH2:17][CH:18]([CH3:21])[CH3:19])=[O:7])[C:3]([C:9]([O:11][CH2:2][CH:3]([CH3:9])[CH3:4])=[O:10])=[CH:2]1

Participants

Reactant 3

HCID 6397Chlorotrimethylsilane

HCID 6560Isobutanol

HCID 255853Thiophene-3,4-dicarboxylic acid

Product 1

HCID 69303861Di-isobutyl thiophene-3,4-dicarboxylateYield 95%

Procedure

A mechanically stirred slurry of 5.00 g of thiophene-3,4-dicarboxylic acid (purchased from Aldrich) in 58.2 mL of 2-methyl-1-propanol was treated with 11.0 mL of chlorotrimethylsilane at room temperature. After completion of the addition, the reaction mixture was stirred at room temperature for 1 h, then at 65° C. for one day, quenched with water at 0° C. and extracted with ether. The combined organic phases were washed with saturated water solution of sodium carbonate, brine, dried over magnesium sulfate, filtered, concentrated on a rotary evaporator, and distilled in vacuum to give 7.86 g (95%) of the title compound of 99.6% GC-purity (bp 113° C./1 mm Hg; colorless oil).