1,2,3,3a,4,5,6,6a-octahydropentalene

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of (E)-6-acetoxy-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxy-3-cyclohexylprop-1-enyl]bicyclo[3,3,0]octane (0.4 g; prepared as described in Example 31 and predominantly in the 2β-configuration), potassium carbonate (0.15 g) and methanol (10 ml) was heated at 50° C. for 8 hours. The mixture was then cooled and concentrated in vacuo. The resulting residue was extracted with dichloromethane (3×5 ml). Concentration in vacuo of the combined extracts gave (E)-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxy-3-cyclohexylprop-1-enyl]-6-hydroxybicyclo[3,3,0]octane, predominantly in the 2β-configuration, in the form of an oil (0.36 g), sufficiently pure enough in the next stage. prepared The mixture was then cooled concentrated in vacuo The resulting residue was extracted with dichloromethane (3×5 ml) Concentration in vacuo of the combined extracts

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of (E)-6-acetoxy-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxy-3-cyclohexylprop-1-enyl]bicyclo[3,3,0]octane (0.4 g; prepared as described in Example 31 and predominantly in the 2β-configuration), potassium carbonate (0.15 g) and methanol (10 ml) was heated at 50° C. for 8 hours. The mixture was then cooled and concentrated in vacuo. The resulting residue was extracted with dichloromethane (3×5 ml). Concentration in vacuo of the combined extracts gave (E)-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxy-3-cyclohexylprop-1-enyl]-6-hydroxybicyclo[3,3,0]octane, predominantly in the 2β-configuration, in the form of an oil (0.36 g), sufficiently pure enough in the next stage. prepared The mixture was then cooled concentrated in vacuo The resulting residue was extracted with dichloromethane (3×5 ml) Concentration in vacuo of the combined extracts

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of (E)-6-acetoxy-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxyoct-1-enyl]bicyclo[3,3,0]octane (530 mg; prepared as described in Reference Example 24 and predominantly in the 2β-configuration) in methanol (10 ml) was treated with anhydrous potassium carbonate (193 mg). The mixture was heated at 40° C., with stirring, for 24 hours. The methanol was then removed in vacuo and the residue was extracted with dichloromethane (3×10 ml). Concentration of the extract in vacuo gave (E)-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxyoct-1-enyl]-6-hydroxybicyclo[3,3,0]octane (430 mg), predominantly in the 2β-configuration. prepared The methanol was then removed in vacuo the residue was extracted with dichloromethane (3×10 ml) Concentration of the extract in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of (E)-6-acetoxy-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxy-3-cyclohexylprop-1-enyl]bicyclo[3,3,0]octane (0.4 g; prepared as described in Example 31 and predominantly in the 2β-configuration), potassium carbonate (0.15 g) and methanol (10 ml) was heated at 50° C. for 8 hours. The mixture was then cooled and concentrated in vacuo. The resulting residue was extracted with dichloromethane (3×5 ml). Concentration in vacuo of the combined extracts gave (E)-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxy-3-cyclohexylprop-1-enyl]-6-hydroxybicyclo[3,3,0]octane, predominantly in the 2β-configuration, in the form of an oil (0.36 g), sufficiently pure enough in the next stage. prepared The mixture was then cooled concentrated in vacuo The resulting residue was extracted with dichloromethane (3×5 ml) Concentration in vacuo of the combined extracts

Conditions: temp:40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of (E)-6-acetoxy-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxyoct-1-enyl]bicyclo[3,3,0]octane (530 mg; prepared as described in Reference Example 24 and predominantly in the 2β-configuration) in methanol (10 ml) was treated with anhydrous potassium carbonate (193 mg). The mixture was heated at 40° C., with stirring, for 24 hours. The methanol was then removed in vacuo and the residue was extracted with dichloromethane (3×10 ml). Concentration of the extract in vacuo gave (E)-2-[(mixture of 3α and 3β)-tert-butyldimethylsilyloxyoct-1-enyl]-6-hydroxybicyclo[3,3,0]octane (430 mg), predominantly in the 2β-configuration. prepared The methanol was then removed in vacuo the residue was extracted with dichloromethane (3×10 ml) Concentration of the extract in vacuo