Formaldehyde → HCID 57849006, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 13.0 g (22.2 mmol) 3-5 in 150 ml of THF at −78° C. was added dropwise a solution of 22.2 ml (44.4 mmol) 2 M NaHMDS in THF. After the addition was complete, the solution was warmed to −40° C. and stirred for 45 min. In a separate flask, 40 g of paraformaldehyde was mixed with 100 ml of mineral oil and heated at 140° C. A stream of argon was passed over the paraformaldehyde/mineral oil mixture and the resulting formaldehyde gas was bubbled into the above solution of C-5 still at −40° C. for 15 minutes. The cold solution was quenched with 100 ml of saturated aqueous NH4Cl and allowed to warm to room temperature. The mixture was dumped into a separatory funnel with EtOAc and the layers were separated. The aqueous was extracted with EtOAc, the combined organics were washed with brine, dried over MgSO4, and concentrated. The residue was purified by silica gel chromatography with EtOAc/hexanes to provide 3-6 as an amber gum. Data for 3-6: LC-MS: rt=3.1 min, m/z=531 (M−THP+1).

Provenance & Evidence