The present invention provides a process for preparing novel intermediates of Formula wherein R1 can be hydrogen C1-C4 alkyl, halogen nitro hydroxy or C1-C4 alkoxy Rx can be selected from hydrophobic residue of HMG CoA reductase inhibitors which can be effectively used for the preparation of HMG CoA reductase inhibitors such as rosuvastatin and pharmaceutically acceptable salts thereof.