methyl (2S)-2-phenylmethoxypropanoate

Conditions: temp:-2.51; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of (S)-methyl 2-(benzyloxy)propanoate compound of formula-14 obtained in example-11 (100 g) and toluene (200 ml) was cooled to −75 to 70° C. under nitrogen atmosphere. DIBAL (500 ml) was added to the reaction mixture and stirred for 3 hours at the same temperature. After completion of the reaction, the reaction mixture was quenched with methanol and 30% hydrochloric acid was added to it at −75 to −70° C. Temperature of reaction mixture was raised to 25-30° C. Both organic and aqueous layers were separated and the aqueous layer was extracted with toluene. Both organic layers were combined, washed with 5% sodium bicarbonate and 10% sodium chloride solution. The organic layer containing title compound is carried for the next step without distillation. After completion of the reaction the reaction mixture was quenched with methanol and 30% hydrochloric acid was added to it at −75 to −70° C Temperature of reaction mixture was raised to 25-30° C Both organic and aqueous layers were separated the aqueous layer was extracted with toluene washed with 5% sodium bicarbonate and 10% sodium chloride solution The organic layer containing title compound is carried for the next step without distillation

Conditions: temp:-2.51; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of (S)-methyl 2-(benzyloxy)propanoate compound of formula-14 obtained in example-11 (100 g) and toluene (200 ml) was cooled to −75 to 70° C. under nitrogen atmosphere. DIBAL (500 ml) was added to the reaction mixture and stirred for 3 hours at the same temperature. After completion of the reaction, the reaction mixture was quenched with methanol and 30% hydrochloric acid was added to it at −75 to −70° C. Temperature of reaction mixture was raised to 25-30° C. Both organic and aqueous layers were separated and the aqueous layer was extracted with toluene. Both organic layers were combined, washed with 5% sodium bicarbonate and 10% sodium chloride solution. The organic layer containing title compound is carried for the next step without distillation. After completion of the reaction the reaction mixture was quenched with methanol and 30% hydrochloric acid was added to it at −75 to −70° C Temperature of reaction mixture was raised to 25-30° C Both organic and aqueous layers were separated the aqueous layer was extracted with toluene washed with 5% sodium bicarbonate and 10% sodium chloride solution The organic layer containing title compound is carried for the next step without distillation

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Dimethyl formamide (0.5 ml) was added to a mixture of (S)-1-phenylethanamine salt of (S)-2-(benzyloxy)propanoic acid compound of formula-13a obtained in step-c) of above examples-9 &. 10 (200 g) and methanol (600 ml) and the reaction mixture was cooled to 0-5° C. Thionyl chloride (58.4 ml) was slowly added to the reaction mixture at 0-5° C. over a period of 1 hour and stirred for 1 hour at 0-10° C. After completion of the reaction, the reaction mixture was quenched with water and extracted with dichloro methane. Both aqueous and dichloro methane layers were separated, dichloro methane layer was washed with 10% sodium chloride and water. Distilled off the solvent completely from dichloro methane layer to get title compound. Yield: 129 g; Chiral purity: 99.5% of formula-13a obtained in step-c) of above examples-9 After completion of the reaction the reaction mixture was quenched with water extracted with dichloro methane Both aqueous and dichloro methane layers were separated dichloro methane layer was washed with 10% sodium chloride and water Distilled off the solvent completely from dichloro methane layer

Conditions: temp:-2.51; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of (S)-methyl 2-(benzyloxy)propanoate compound of formula-14 obtained in example-11 (100 g) and toluene (200 ml) was cooled to −75 to 70° C. under nitrogen atmosphere. DIBAL (500 ml) was added to the reaction mixture and stirred for 3 hours at the same temperature. After completion of the reaction, the reaction mixture was quenched with methanol and 30% hydrochloric acid was added to it at −75 to −70° C. Temperature of reaction mixture was raised to 25-30° C. Both organic and aqueous layers were separated and the aqueous layer was extracted with toluene. Both organic layers were combined, washed with 5% sodium bicarbonate and 10% sodium chloride solution. The organic layer containing title compound is carried for the next step without distillation. After completion of the reaction the reaction mixture was quenched with methanol and 30% hydrochloric acid was added to it at −75 to −70° C Temperature of reaction mixture was raised to 25-30° C Both organic and aqueous layers were separated the aqueous layer was extracted with toluene washed with 5% sodium bicarbonate and 10% sodium chloride solution The organic layer containing title compound is carried for the next step without distillation

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Dimethyl formamide (0.5 ml) was added to a mixture of (S)-1-phenylethanamine salt of (S)-2-(benzyloxy)propanoic acid compound of formula-13a obtained in step-c) of above examples-9 &. 10 (200 g) and methanol (600 ml) and the reaction mixture was cooled to 0-5° C. Thionyl chloride (58.4 ml) was slowly added to the reaction mixture at 0-5° C. over a period of 1 hour and stirred for 1 hour at 0-10° C. After completion of the reaction, the reaction mixture was quenched with water and extracted with dichloro methane. Both aqueous and dichloro methane layers were separated, dichloro methane layer was washed with 10% sodium chloride and water. Distilled off the solvent completely from dichloro methane layer to get title compound. Yield: 129 g; Chiral purity: 99.5% of formula-13a obtained in step-c) of above examples-9 After completion of the reaction the reaction mixture was quenched with water extracted with dichloro methane Both aqueous and dichloro methane layers were separated dichloro methane layer was washed with 10% sodium chloride and water Distilled off the solvent completely from dichloro methane layer