Method for producing enantiomeric form of 2,3-diaminopropionic acid derivatives

A process for obtaining a compound of the formula I:

• where:
• R1 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• —(C6-C14)-aryl where aryl is unsubstituted or mono-, di- or trisubstituted independently by R11,
• where R11 is:
• F, Cl, I or Br,
• —(C1-C4)-alkyl,
• —CN,
• —CF3,
• —OR5 in which R5 is a hydrogen atom or —(C1-C4)-alkyl,
• —N(R5)—R6 in which R5 and R6 are each independently a hydrogen atom or —(C1-C4)-alkyl,
• —C(O)—R5 in which R5 is a hydrogen atom or —(C1-C4)-alkyl, or
• —S(O)x—R5 in which x is the integer zero, 1 or 2, and R5 is a hydrogen atom or —(C1-C4)-alkyl;
• —CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine, where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• or
• a 4- to 15-membered Het ring where the Het ring is unsubstituted or mono-, di- or trisubstituted independently by —(C1-C5)-alkyl, —(C1-C5)-alkoxy, halogen, nitro, amino, trifluoro-methyl, hydroxyl, hydroxy-(C1-C4)-alkyl, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl, amino-carbonyl or —(C1-C4)-alkoxycarbonyl;
• R2 is:
• —(C6-C14)-aryl where aryl is unsubstituted or mono-, di- or trisubstituted independently by R11;
• —CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine, where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• or
• a 4- to 15-membered Het ring where the Het ring is unsubstituted or mono-, di- or trisubstituted independently by —(C1-C5)-alkyl, —(C1-C5)-alkoxy, halogen, nitro, amino, trifluoromethyl, hydroxyl, hydroxy-(C1-C4)-alkyl, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl, aminocarbonyl or —(C1-C4)-alkoxycarbonyl;
• R3 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• —(C6-C14)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—(C1-C4)-alkyl, F, Cl or bromine;
• —O—C(CH3)3;
• or
• —O—CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine,
• where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• R4 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• or
• —CH(R8)-aryl;
• in which R8 is a hydrogen atom or —(C1-C4)-alkyl,
• said process comprising the step of:
• hydrogenating a compound of the formula II
• in which R1, R2, R3 and R4 are each as defined in the formula I and the compound of the formula II may be present in the E or in the Z configuration on the double bond,
• in the presence of hydrogen and a catalyst.

A process for obtaining a compound of formula III:

• or salts thereof, where:
• R1 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• —(C6-C14)-aryl where aryl is unsubstituted or mono-, di- or trisubstituted independently by R11,
• where R11 is:
• F, Cl, I or Br,
• —(C1-C4)-alkyl,
• —CN,
• —CF3,
• —OR5 in which R5 is a hydrogen atom or —(C1-C4)-alkyl,
• —N(R5)—R6 in which R5 and R6 are each independently a hydrogen atom or —(C1-C4)-alkyl,
• —C(O)—R5 in which R5 is a hydrogen atom or —(C1-C4)-alkyl, or
• —S(O)x—R5 in which x is the integer zero, 1 or 2, and R5 is a hydrogen atom or —(C1-C4)-alkyl;
• —CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine, where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• or
• a 4- to 15-membered Het ring where the Het ring is unsubstituted or mono-, di- or trisubstituted independently by —(C1-C5)-alkyl, —(C1-C5)-alkoxy, halogen, nitro, amino, trifluoro-methyl, hydroxyl, hydroxy-(C1-C4)-alkyl, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl, amino-carbonyl or —(C1-C4)-alkoxycarbonyl;
• R2 is:
• —(C6-C14)-aryl where aryl is unsubstituted or mono-, di- or trisubstituted independently by R11;
• —CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine, where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• or
• a 4- to 15-membered Het ring where the Het ring is unsubstituted or mono-, di- or trisubstituted independently by —(C1-C5)-alkyl, —(C1-C5)-alkoxy, halogen, nitro, amino, trifluoromethyl, hydroxyl, hydroxy-(C1-C4)-alkyl, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl, aminocarbonyl or —(C1-C4)-alkoxycarbonyl;
• R3 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• —(C6-C14)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—(C1-C4)-alkyl, F, Cl or bromine;
• —O—C(CH3)3;
• or
• —O—CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine,
• where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• R4 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• or
• —CH(R8)-aryl;
• in which R8 is a hydrogen atom or —(C1-C4)-alkyl,
• said process comprising the steps of:
• a) hydrogenating the compound of the formula II:
• in which:
• R1 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• —(C6-C14)-aryl where aryl is unsubstituted or mono-, di- or trisubstituted independently by R11,
• where R11 is:
• F, Cl, I or Br,
• —(C1-C4)-alkyl,
• —CN,
• —CF3,
• —OR5 in which R5 is a hydrogen atom or —(C1-C4)-alkyl,
• —N(R5)—R6 in which R5 and R6 are each independently a hydrogen atom or —(C1-C4)-alkyl,
• —C(O)—R5 in which R5 is a hydrogen atom or —(C1-C4)-alkyl, or
• —S(O)x—R5 in which x is the integer zero, 1 or 2, and R5 is a hydrogen atom or —(C1-C4)-alkyl;
• —CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine, where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• or
• a 4- to 15-membered Het ring where the Het ring is unsubstituted or mono-, di- or trisubstituted independently by —(C1-C5)-alkyl, —(C1-C5)-alkoxy, halogen, nitro, amino, trifluoro-methyl, hydroxyl, hydroxy-(C1-C4)-alkyl, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl, amino-carbonyl or —(C1-C4)-alkoxycarbonyl;
• R2 is:
• —(C6-C14)-aryl where aryl is unsubstituted or mono-, di- or trisubstituted independently by R11;
• —CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine, where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• or
• a 4- to 15-membered Het ring where the Het ring is unsubstituted or mono-, di- or trisubstituted independently by —(C1-C5)-alkyl, —(C1-C5)-alkoxy, halogen, nitro, amino, trifluoromethyl, hydroxyl, hydroxy-(C1-C4)-alkyl, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl, aminocarbonyl or —(C1-C4)-alkoxycarbonyl;
• R3 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• —(C6-C14)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—(C1-C4)-alkyl, F, Cl or bromine;
• —O—C(CH3)3;
• or
• —O—CH(R7)-aryl in which aryl is unsubstituted or mono-, di- or trisubstituted independently
• by —NO2, —O—CH3, F, Cl or bromine,
• where R7 is a hydrogen atom or —(C1-C4)-alkyl;
• R4 is:
• a hydrogen atom;
• —(C1-C4)-alkyl;
• or
• —CH(R8)-aryl;
• in which R8 is a hydrogen atom or —(C1-C4)-alkyl,
• in the presence of hydrogen and a catalyst, and converting it to a compound of the formula I
• and
• b) converting the resulting compound of the formula I to a compound of the formula III.