Processes and intermediates for the preparations of prostaglandins

A process for preparing the compounds of Formula II, having an enantiomeric purity higher than 95% enantiomeric excess:

• wherein Z is an arbitrary group that does not participate in a coupling and deprotection reactions but acts as a leaving group in a reduction/lactonization reaction;
• R2 is a single bond or a C1-4-alkylene or —CH2O—;
• R3 is a C1-7-alkyl or an aryl or an aralkyl, each of which is unsubstituted or substituted by a C1-4-alkyl, a halogen or a trihalomethyl;
• X1 and X2 are independently hydrogen or are P1 and P2, respectively, where P1 and P2 are the same or different protecting groups for the hydroxyl groups;
• and is a single bond or a double bond, comprising reacting compounds of Formula IV having an optical purity higher than 90% enantiomeric excess:
• wherein P1 is as defined above, with a cuprate derived from the compound of Formula V-1, Formula V-2 or Formula V-3, each of which having an optical purity higher than 90% enantiomeric excess:
• wherein Y is a halogen;
• R6 is a lower alkyl;
• and R2, R3, and P2 are as defined above;
• and optionally conducting a deprotection reaction of the esultant compound to convert P1 or P2 or both P1 and P2 to H.

The compound of claim 11 selected from the group consisting of:

• Ethyl(1R,2R,3R)-3-hydroxy-2-[(3S)-hydroxy-(1E)-octenyl]-5-oxo-cyclopentane acetate;
• Benzyl(1R,2R,3R)-3-hydroxy-2-[(3S)-hydroxy-(1E)-octenyl]-5-oxo-cyclopentane acetate;
• 2-Naphthyl(1R,2R,3R)-3-hydroxy-2-[(3S)-hydroxy-(1E)-octenyl]-5-oxo-cyclopentane acetate;
• (1′R,2′S,5′R)-Menthyl(1R,2R,3R)-3-hydroxy-2-[(3S)-hydroxy-(1E)-octenyl]-5-oxo-cyclopentane acetate;
• 2-Cyanoethyl
• (1R,2R,3R)3-hydroxy-2-[(3S)-hydroxy-(1E)-octenyl]-5-oxo-cyclopentane acetate;
• 3-Ethoxycarbonylphenyl(1R,2R,3R)-3-hydroxy-2-[(3S)-hydroxy-(1E)-octenyl]-5-oxo-cyclopentane acetate;
• 4-Morpholineethyl(1R,2R,3R)-3-hydroxy-2-[(3S)-hydroxy-(1E)-octenyl]-5-oxo-cyclopentane acetate;
• Benzyl(1R,2R,3R)-3-hydroxy-2-[5-phenyl-(3S)-hydroxy-(1E)-pentenyl]-5-oxo-cyclopentane acetate;
• 2-Naphthyl(1R,2R,3R)-3-hydroxy-2-[5-phenyl-(3S)-hydroxy-(1E)-pentenyl]-5-oxo-cyclopentane acetate;
• (1′R,2′S,5′R)-Menthyl(1R,2R,3R)-3-hydroxy-2-[5-phenyl-(3S)-hydroxy-(1E)-pentenyl]-5-oxo-cyclopentane acetate;
• Ethyl(1R,2R,3R)3-hydroxy-2-[5-phenyl-(3S)-hydroxy-1-pentenyl]-5-oxo-cyclopentane acetate;
• Ethyl(1R,2R,3R)-3-hydroxy-2-[(3R)-hydroxy-4-(3-trifluoromethyl)phenoxy-(1E)-butenyl]-5-oxo-cyclopentane acetate;
• and Ethyl(1R,2R,3R)3-hydroxy-2-[5-phenyl-(3R)-hydroxy-pentanyl]-5-oxo-cyclopentane acetate.