Formaldehyde → 5-(Tetrahydro-pyran-2-yloxy)-pent-2-yn-1-ol

Participants

Reaction Conditions

Reaction Steps

To a solution of 8.0 mL (51 mmol) of 2-(3-butynyloxy)tetrahydro-2H-pyran in 150 mL of THF under nitrogen atmosphere at −23° C. was added dropwise a solution of 33 mL (53 mmol) of 1.6M butyllithium in hexanes, maintaining the temperature at −23° C. The resulting solution was stirred at 0° C. for 2 h, recooled to −23° C. and 2.4 g (76.5 mmol) of paraformaldehyde was added in several portions. The mixture was stirred at −23° C. for 1 h and let warm to room temperature and stirred for 18 h. The reaction mixture was poured into a large excess of ice water and extracted with ether. The organics were washed with brine until neutral, dried over MgSO4, filtered and concentrated in vacuo. The residue was kugelrohr distilled to provide 7.26 g (77%) of 5-(tetrahydro-2H-pyran-2-yloxy)-2-pentyn-1-ol as a colorless liquid. EI Mass Spec: 185.1 (M+H)+.

Provenance & Evidence