Methyl iodide → 3-Bromo-2-methyl-thieno[3,2-b]pyridine

Participants

Reaction Conditions

Reaction Steps

674 mg of 3-Bromo-thieno[3,2-b]pyridine (3.15 mmol) is dissolved in 12 ml of dry THF and cooled to −78° C. 2.3 ml of LDA-mono-tetrahydrofuran (1.5 M) solution in cyclohexane (3.46 mmol) is added to the mixture at −78° C. and stirred at −78° C. for 20 min. 0.22 ml of methyliodide (3.46 mmol) is added to the mixture and stirred at −78° C.→room temperature for 2 h. the reaction mixture is quenched by sat. NH4Cl and extracted with CH2Cl2. The separated CH2Cl2 is dried over Na2SO4 and evaporated. The crude product is applied onto a silica-gel chromatography column (Hexane:AcOEt:2 M NH3 in MeOH=20:4:1) to give 618 mg of the title compound. Yield 86%. mass spectrum (m/e): 230 (M+1); 1H-NMR (CDCl3): 8.78 (dd, 1H, J=4.8 Hz, 1.4 Hz), 8.10 (dd, 1H, J=8.2 Hz, 1.4 Hz), 7.30 (dd, 1H, J=8.2 Hz, 4.8 Hz), 2.67 (s, 3H).

Provenance & Evidence