Dimethyl Sulfate → 5-methyl-[2,2']bithiophene

Participants

Reaction Conditions

Reaction Steps

Under a nitrogen atmosphere a stirred solution of 32.0 grams (0.193 mole) of 2,2'-bithienyl in 150 mL of diethyl ether was cooled to -5°0 C., and 90.5 mL (0.226 mole--2.6M in hexanes) of n-butyllithium was added slowy dropwise. Upon completion of addition the reaction mixture was stirred at -5° C. for one hour, and then a solution of 27.8 grams (0.220 mole) of dimethylsulfate in 75 mL of diethyl ether was added very slowly dropwise. Upon completion of addition the reaction mixture was allowed to warm to ambient temperature where it stirred for 18 hours. After this time the reaction mixture was poured into 350 mL of an aqueous 10% ammonium chloride solution. The mixture was extracted with diethyl ether, and the combined extracts were washed with water. The organic layer was dried with magnesium sulfate and filtered. The filtrate was concentrated under reduced pressure to a residual oil. The oil was distilled under reduced pressure to yield 30.0 grams of 5-methyl(2,2'-bithienyl); b.p. 108°-113° C./1.9 mm.

Provenance & Evidence