1.4- Acetoxy trifluoroacetoxylation

The 1,4-diacetoxylation was also extended to the use of other acyl groups than acetyl. Thus, an unsymmetrical 1,4-acetoxy-trifluoroacetoxylation of 1,3-dienes was developed by the use of added trifluoroacetic acid to the acetic acid used as the solvent330. With the use of acetone as the solvent with an added carboxylic acid a general diacyloxylation was obtained and, for example, the 1,4-dibenzoates of 2-cycloalkene-l,4-diols were prepared directly from the corresponding l,3-cycloalkadienes33d. 

C.i.a. 1,4-Addition of Two Oxygen Nucleophiles. Efficient procedures for 1,4-diacetoxy-lation, 1,4-chloroacetoxylation, and 1,4-dialkoxylation were reported in the 1980s. In the latter reactions nucleophiles were introduced in the 1- and 4-positions.f f f An important issue is to introduce two different nucleophiles in the 1- and 4-positions, respectively. Synthetically useful procedures for the 1,4-acetoxy-trifluoroacetoxylation and 1,4-alkoxy-trifluoroace-toxylation were recently reported (Eqs. 6 and 7). ... 

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