Methyl iodide → 3,3-Dimethyloxan-2-one

Participants

Reaction Conditions

Reaction Steps

The 3-methyltetrahydro-2H-pyran-2-one from Example 4(a) (5.6 g, 49.0 mmol) was slowly added to a cold (-78° C.) THF solution (50 ml) of LDA (54 mmol) so that the internal temperature did not exceed -65° C. After stirring for an additional 30 minutes, the acetone/CO2 bath was replaced with a CH3CN/CO2 bath and CH3I (10.4 g, 73.5 mmol) was added at a rate sufficient to maintain the internal temperature at -45° C. After stirring at -45° C. for an additional hour the reaction was allowed to warm to -30° C. and quenched by the dropwise addition of 10% HCl (21 ml). The resulting mixture was poured into ether (300 ml) and the ether layer was washed with saturated brine (50 ml), saturated NaHCO3 solution (20 ml), saturated brine (2×25 ml), dried (MgSO4) and evaporated to provide a pale yellow oil. This oil was distilled to give the title compound as a colorless liquid. b.p.0.2 54° C. NMR (CDCl3) δ 4.34 (2 H, m), 1.89 (2 H, m), 1.75 (2 H, m), 1.30 (6H, s).

Provenance & Evidence