Process for the preparation of hmg-coa reductase inhibitors and intermediates thereof

A process for preparing a compound of Formula 1, comprising converting a compound of Formula 4 to a compound of Formula 1:

• wherein,
• M is an alkali metal or an alkaline earth metal,
• R1 and R2 are independently C1˜C5 alkyl or aryl,
• P1 and P2 are independently an alcohol-protecting group;
• or P1 and P2 are cyclized each other to form a 1,3-diol protecting group selected from the group consisting of:
• wherein R9 and R10 are independently C1˜C10 alkyl or R9 and R10 are cyclized each other to form a pentane ring, a hexane ring, or a heptane ring;
• Z is oxygen or sulfur;
• and Ph is phenyl, and
• Het is