Borane;tetrahydrofuran → (5-Chloropyridin-2-yl)methanol

Beteiligte Stoffe

Reaktionsschritte

5-Chloropyridine-2-carboxylic acid (2.00 g, 12.7 mmol) was dissolved in THF (12 mL) at 0° C. and added to a solution of borane-THF (19.0 mL, 1 M in THF, 19.0 mmol). THF (10 mL) was added and the reaction mixture was warmed to room temperature, stirred for 2 h and heated under reflux at 70° C. for 3 h. The reaction mixture was cooled to 0° C., quenched with aq 6 M HCl solution (4 mL) and the solution was stirred for 2 h and concentrated in vacuo. The residue was partitioned between H2O (75 mL) and DCM (75 mL). The aq layer was washed with DCM (3×75 mL), adjusted to pH 9 with 4 M aq NaOH (3 mL) and extracted with DCM (3×75 mL). The organic layers were combined, dried (MgSO4) and concentrated in vacuo to give 5-chloropyridine-2-methanol (0.83 g, 45%) as a brown gum.

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