Process and intermediates for preparing pregabalin

A compound of formula (VI) ** ** Formula wherein R is selected from hydrogen, (C1-C6), haloalkyl (C1-C6) alkyl, (C1-C3) alkyl (C2-C6), (C2-C6), cycloalkyl (C3-C10), which may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and (C1-C3), (C3-C10 ) (C1-C6), wherein the cycloalkyl group may be optionally substituted with 1, 2 or 3 independently selected from halo, (C1-C3) and (C1-C3), aryl which may be optionally groups substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and (C1-C3), aryl (C1-C6), wherein the aryl group may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and (C1-C3), R1-C (O) -, and R2-SO2-; R1 is selected from: hydrogen, (C1-C6), haloalkyl (C1-C6) alkyl, (C1-C3) alkyl (C2-C6), alkenyl (C2-C6), cycloalkyl (C3-C10), which may optionally be substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and (C1-C3), (C3-C10) (C1-C6), wherein the cycloalkyl group may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and (C1-C3), aryl which may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1 -C3) and (C1-C3), and aryl (C1-C6), wherein the aryl group may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and alkyloxy ( C1-C3); and R2 is selected from: (C1-C6), haloalkyl (C1-C6) alkyl, (C1-C3) alkyl (C2-C6), alkenyl (C2-C6), cycloalkyl (C3-C10), which may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and (C1-C3), (C3-C10) (C1-C6), wherein the cycloalkyl group may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and (C1-C3), aryl which may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1- C3) and (C1-C3) and aryl (C1-C6), wherein the aryl group may be optionally substituted with 1, 2 or 3 groups independently selected from halo, (C1-C3) and alkyloxy (C1- C3).