2- Cycloalkene-l,4-diols

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. 

Cycloalkene-l,4-diols, 608-609 Cycloalkenes, 162,417-418 Cyclobutadiene, 55, 149 Cyclobutadiene iron tricarbonyl, 55, 149-... 

The ring opening of endoperoxides by Grignard reagents and related organometallics is interesting, as monoethers of ct r-2-cycloalkene-l,4-diols are formed. 

Participation of nucleophiles in the cyclization of enynes gives rise to functionalized products. Thus, substrates containing an allylic carbonate unit are transformed into derivatives of 4-cycloalkene-l,2-diols. Without an internally participatory group an enyne can incorporate an amine. 

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