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Reactions of vinyl ethers, N-vinyl carboxamides and N-vinyl sulfonamides with trifluoroacetic (or trichloroacetic) anhydride occurred quite easily at room temperature to give corresponding β-trifluoro- or trichloroacetylated compounds in high yields. Reactions with a mixed anhydride, CH3COOCOCF3, gave trifluoroacetylated compounds in high yields, acetyl compounds being not produced.
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Hojo et al. (1976) studied this question.
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