Patent ID: 8269001

Claim:
A process for manufacturing rosuvastatin, characterized in that it comprises steps: a) (optionally) reacting alkyl 3(S)-hydroxy-4-chlorobutyrate of formula I, wherein R 2 is an optionally substituted C 1 -C 8 alkyl or C 5 -C 7 cycloalkyl, or alternatively, —COOR 2 may also form an amide of formula —CONR a ,R b , where R a and R b may independently be H, an optionally substituted C 1 -C 8 alkyl or C 5 -C 7 cycloalkyl, aryl or can together with N form a heterocycle with an iodide to give an alkyl 3(S)-hydroxy-4-iodobutyrate of formula II wherein R 2 is as above; b) (optionally) protecting the compound of formula II to give a protected derivative of formula III, wherein R 1 and R 2 are as above; c) reacting the compound of formula III with vinylmagnesium halide in presence of copper(I) halide and phosphite derivative with formula: where each of R′, R″, and R′″ are same or different C 1 -C 4 alkyl, C 5 -C 7 cycloalkyl, or aryl which may be optionally substituted to give an alkene of formula IV wherein R 1 and R 2 are as above; d) hydrolyzing the compound of formula IV to give compound of formula V e) reacting compound of formula V, wherein R 1 is as above, with a source of halogen in the presence of NaHCO 3 to give compound of formula VI; f) (optionally) separating the mixture of diastereoisomers obtained in previous step to obtain compound of formula VIa wherein X″ is halo and R 1 as above; g) converting the compound of formula VIa into compound of formula VII, wherein R 1 is as above and R 4 is selected from (optionally halo or alkoxy or aryloxy substituted) C 1 -C 4 alkyl; h) converting compound of formula VII in compound of formula VIII wherein R 1 is as above; i) converting the compound of formula VIII by oxidation into compound of formula IX, wherein R 1 is as above; j) reacting said compound of formula IX with the compound of formula wherein Rx, Ry, and Rz are the same or different and are selected from optionally substituted C 1 -C 8 alkyl or C 3 -C 6 cycloalkyl or C 1 -C 8 alkenyl or C 5 -C 6 cycloalkenyl or aryl, X − is anion; and k) removing the protecting group R 1 , optionally purifying and converting the obtained compound into calcium salt.