p-Toluenesulfonic acid → (1S,5R,6R,7R)-6-(3,3-ethylenedioxyoctyl)-7-tetrahydropyranyloxy-2-oxabicyclo[3.3.0]octan-3-one

Participants

Reaction Steps

A solution cf (1S,5R,6R,7R)-6-(3,3-ethylenedioxyoctyl)-7-hydroxy-2-oxabicyclo[3.3.0]octan-3-one (6a) (4 70 g) in dichloromethane (200 ml) was cooled on ice and dihydropyran (2.41 g) and p-toluenesulfonic acid (0.23 g) were added thereto and the resultant mixture was stirred for 1,5 hours. The crude product obtained by treating in the conventional manner was subjected to silica gel column chromatography to give the title compound (59).

Provenance & Evidence