Sodium Carbonate → 5-Methyl-3-oxocyclohex-1-en-1-yl trifluoromethanesulfonate

Participants

Reaction Conditions

Reaction Steps

To a solution of 5-methylcyclohexane-1,3-dione (1 equiv) in DCM (0.4M) was added Na2CO3 (1.0 equiv.) and cooled to 0° C. Added Tf2O (1.0 equiv.) in DCM (5M) dropwise over 1 hr at 0° C. under a nitrogen atmosphere. Upon addition, the reaction was stirred for 2 hr at room temperature (dark red solution). The solution was filtered and to the filtrate was added saturated NaHCO3 (carefully), then extracted the organics, dried with brine, then Na2SO4, and concentrated. The crude was purified via SiO2 column chromatography eluting with DCM and hexanes (1:1) or alternatively via a neutral alumina plug eluting with DCM to afford 5-methyl-3-oxocyclohex-1-enyl trifluoromethanesulfonate in 30% or 67% yield respectively. The triflate decomposes upon storage and should be used immediately for the next reaction. LC/MS=259.1/300.1 (M+H and M+CH3CN); Rt=0.94 min, LC=3.84 min.

Provenance & Evidence