Process for production of (+)-2-amino-1-butanol

Claim 1

A process for producing (+)-2-amino-1-butanol which comprises 1. optically resolving an N-acyl-DL-2-aminobutyric acid in an aqueous solution using the action of an acylase to obtain (A) an aqueous solution predominantly comprising L-2-aminobutyric acid and a small amount of an N-acyl-D-2-aminobutyric acid and (B) an aqueous solution predominantly comprising an N-acyl-D-2-aminobutyric acid and a small amount of L-2-aminobutyric acid, 2. isolating crystalline L-2-aminobutyric acid from said solution (A) and to obtain a solution (C) from which said L-2-aminobutyric acid has been isolated, 3. esterifying said crystalline L-2-aminobutyric acid to form an L-2-aminobutyric acid ester, 4. reducing the L-2-aminobutyric acid ester to form (+)-2-amino-1-butanol, said reducing occurring in the presence of Raney nickel in an amount higher than about 50% by weight or platinum in an amount higher than about 10% by weight based on the amount of said L-2-aminobutyric acid ester at temperatures of ambient temperature to about 70°C and a hydrogen pressure below about 70 Kg/cm 2 5. combining said solution (B) and said solution (C) to form a solution (D), 6. crystallizing said N-acyl-D-2-aminobutyric acid from said solution (D) to obtain crystals comprising predominantly said N-acyl-D-2-aminobutyric acid and a small amount of said L-2-aminobutyric acid, and