Process for preparing 2,2'-diaminobiaryls, comprising the process steps of: a) reacting a compound of the formula ( IVa) or ( Va): with reaction of ( IVa) to give or, or of ( Va) to give ( Vb): b) reacting a compound of the formula ( VIa) or ( VIIa): with reaction of ( VIa) to give ( VIb), or of ( VIIa) to give ( VIIb1) or ( VIIb2): c) electrochemical coupling of: - with ( VIb) to give ( I*), or - with ( VIIb1) to give ( II*), or - ( Vb) with ( VIIb2) to give ( III*), in each case with use of the compound having the higher oxidation potential in excess: where R 11, R 12, R 13, R 14, R 11', R 12', R 13', R 14' are selected from: -H, - (C 1 -C 12) -alkyl, -0- (C 1 -C 12) -alkyl, -0- (C 6 -C 20) -aryl, -(C 6 -C 20) -aryl, -S-alkyl, -S-aryl, halogen, -COO- (C 1 -C 12) -alkyl,-CONH- (C 1 -C 12) -alkyl, -CO- (C 1 -C 12) -alkyl, -CO- (C 6 -C 20) -aryl,-COOH, -OH, -SO 3 H, -CN, -N[(C 1 -C 12) -alkyl] 2; R 15, R 16, R 17, R 18, R 19, R 20, R 15', R 16', R 17', R 18', R 19', R 20' are selected from: -H, - (C 1 -C 12) -alkyl, -0- (C 1 -C 12) -alkyl, -0- (C 6 -C 20) -aryl, -(C 6 -C 20) -aryl, -S-alkyl, -S-aryl, halogen, -COO-(C 1 -C 12) -alkyl,-CONH- (C 1 -C 12) -alkyl, -CO- (C 1 -C 12) -alkyl, -CO- (C 6 -C 20) -aryl,-COOH, -OH, -SO 3 H, -N[(C 1 -C 12) -alkyl] 2; where the alkyl and aryl groups mentioned may be substituted; X 11 and X 11' are selected from: tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 11 is not the same radical as X 11'; X 12 and X 12' are selected from: tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 12 is not the same radical as X 12'; X 13 and X 13' are selected from: tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 13 is not the same radical as X 13'. a) reacting a compound of the formula ( IVa) or ( Va): with reaction of ( IVa) to give or, or of ( Va) to give ( Vb): b) reacting a compound of the formula ( VIa) or ( VIIa): with reaction of ( VIa) to give ( VIb), or of ( VIIa) to give ( VIIb1) or ( VIIb2): c) electrochemical coupling of: - with ( VIb) to give ( I*), or - with ( VIIb1) to give ( II*), or - ( Vb) with ( VIIb2) to give ( III*), - with ( VIb) to give ( I*), or - with ( VIIb1) to give ( II*), or - ( Vb) with ( VIIb2) to give ( III*), R 11, R 12, R 13, R 14, R 11', R 12', R 13', R 14' are selected from: -H, - (C 1 -C 12) -alkyl, -0- (C 1 -C 12) -alkyl, -0- (C 6 -C 20) -aryl, -(C 6 -C 20) -aryl, -S-alkyl, -S-aryl, halogen, -COO- (C 1 -C 12) -alkyl,-CONH- (C 1 -C 12) -alkyl, -CO- (C 1 -C 12) -alkyl, -CO- (C 6 -C 20) -aryl,-COOH, -OH, -SO 3 H, -CN, -N[(C 1 -C 12) -alkyl] 2; R 15, R 16, R 17, R 18, R 19, R 20, R 15', R 16', R 17', R 18', R 19', R 20' are selected from: -H, - (C 1 -C 12) -alkyl, -0- (C 1 -C 12) -alkyl, -0- (C 6 -C 20) -aryl, -(C 6 -C 20) -aryl, -S-alkyl, -S-aryl, halogen, -COO-(C 1 -C 12) -alkyl,-CONH- (C 1 -C 12) -alkyl, -CO- (C 1 -C 12) -alkyl, -CO- (C 6 -C 20) -aryl,-COOH, -OH, -SO 3 H, -N[(C 1 -C 12) -alkyl] 2; where the alkyl and aryl groups mentioned may be substituted; -H, - (C 1 -C 12) -alkyl, -0- (C 1 -C 12) -alkyl, -0- (C 6 -C 20) -aryl, -(C 6 -C 20) -aryl, -S-alkyl, -S-aryl, halogen, -COO-(C 1 -C 12) -alkyl,-CONH- (C 1 -C 12) -alkyl, -CO- (C 1 -C 12) -alkyl, -CO- (C 6 -C 20) -aryl,-COOH, -OH, -SO 3 H, -N[(C 1 -C 12) -alkyl] 2; where the alkyl and aryl groups mentioned may be substituted; X 11 and X 11' are selected from: tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 11 is not the same radical as X 11'; tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 11 is not the same radical as X 11'; X 12 and X 12' are selected from: tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 12 is not the same radical as X 12'; tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 12 is not the same radical as X 12'; X 13 and X 13' are selected from: tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 13 is not the same radical as X 13'. tert-butyloxycarbonyl, methyloxycarbonyl, benzyloxycarbonyl, phenyloxycarbonyl, acetyl, trifluoroacetyl, benzoyl, sulphonyl, sulphenyl, and X 13 is not the same radical as X 13'.