methyl (2R)-3-[(2-methylpropan-2-yl)oxy]-2-(phenylmethoxycarbonylamino)propanoate

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

Procedure: 330.0 L of methanol was added and 66.0 kg of (R)-methyl 2-(benzyloxycarbonylamino)-3-t-butoxypropanoate was added to a hydrogen reactor; and then purged with nitrogen. 4.95 kg of palladium/carbon (10% water mixture) was added and hydrogen was filled to maintain at 5 bar of pressure. It was stirred for 60 minutes, filtered, washed, and then concentrated under reduced pressure. 132.0 L of ethyl acetate and 88 L of water were added to a concentrated residue; stirred for 10 minutes; an organic layer was isolated (in 6 times), dehydrated, and then concentrated under reduced pressure to obtain 27.5 kg of a title compound. and then purged with nitrogen 4.95 kg of palladium/carbon (10% water mixture) was added hydrogen was filled to maintain at 5 bar of pressure filtered washed concentrated under reduced pressure 132.0 L of ethyl acetate and 88 L of water were added to a concentrated residue stirred for 10 minutes an organic layer was isolated (in 6 times) concentrated under reduced pressure

Conditions: temp:22.51; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 130 L of methylene chloride was added; 20.5 g of (R)-methyl 2-(benzyloxycarbonylamino)-3-hydroxypropanate to a reactor; then stirred for 30 minutes; and then 0.4 kg of sulfuric acid was added. Isobutylene gas was bubbled for 24 hours while its temperature was maintained at 20-25° C. After completing the reaction, 18 L of saturated sodium hydrogen carbonate aqueous solution was slowly added, stirred for 1 hour, and then an organic layer was isolated. 5 kg of sodium sulfate was added to the organic layer, stirred for 1 hour, filtered, washed, and then the filtrate was concentrated under reduced pressure to obtain 29.3 kg of a title compound. Isobutylene gas was bubbled for 24 hours while its temperature the reaction, 18 L of saturated sodium hydrogen carbonate aqueous solution was slowly added stirred for 1 hour an organic layer was isolated stirred for 1 hour filtered washed the filtrate was concentrated under reduced pressure