Reactivity of α-trifluoromethanesulfonyl esters, amides and ketones: Decarboxylative allylation, methylation, and enol formation

• Allylic esters of α-trifluoromethanesulfonylacetate readily underwent palladium-catalyzed decarboxylative allylation.
• α-Trifluoromethanesulfonyl ketones and amides were O-methylated with very high regio- and stereoselectivity by trimethylsilyldiazomethane.
• α-Trifluoromethanesulfonyl ketones exhibited significant enol content in a variety of solvents.

The impact of α-trifluoromethanesulfonyl groups on the chemistry of various carbonyl groups is reported. Allylic α,α-dialkylated-α-trifluoromethanesulfonyl esters readily underwent decarboxylative allylation. α-Trifluoromethylsulfonyl esters, ketones, and amides were all methylated in the presence of trimethylsilyldiazomethane. Esters afforded a mixture of O- and C-methylation; however, ketones and amides offered exclusively O-methylation, with varying degrees of E/Z selectivity, thus affording ambiphilic alkenes. α-Trifluoromethanesulfonyl ketones also exhibited keto-enol tautomerism.

Figure optionsDownload as PowerPoint slide