Process and intermediate compounds useful in the preparation of statins, particularly atorvastatin

Abstract From the Canadian patent

There is provided a process for the preparation of a compound of formula (7) or salts thereof: wherein R1 represents a hydrogen or a hydrocarbyl group R2 , represents a hydrogen or substituent group R3 represents a hydrogen or a , hydrocarbyl group and X represents a hydrogen or substituent group which comprises a) cyanating a compound of formula (1): wherein Y represents a halo group, preferably CI or Br; P1 represents hydrogen or a protecting group and , W represents =0 or -OP2, in which P2 represents hydrogen or a protecting group, to give a compound of formula (2): b) reducing the compound of formula (2) to give a compound of formula (3): coupling the compound of formula (3) with …