Production method for biarylalanine

There is provided a method for producing a biarylalanine compound of formula (4): wherein R 1 represents an amino protective group, and R 2 represents an amino protective group or a hydrogen atom, R 3 is a carboxy protective group, or said amino protective and carboxy protective groups together form an amino acid protective group, and R 4 is a substituted or unsubstituted aryl or heteroaryl group, which comprises reacting an aromatic amino acid of formula (1): wherein X is a halogen atom or a trifluoromethanesulfonyloxy group, and R 1 , R 2 and R 3 are the same as defined above, with an organic boron compound of formula (2): wherein R 4 has the same meaning as defined above, and Q 1 and Q 2 are the same or different and independently represent a hydroxy group or an alkoxy group having 1 to 4 carbon atoms, or Q 1 and Q 2 together form an alkylenedioxy or 1,2-phenylenedioxy group optionally substituted by an alkyl group having 1 to 4 carbon atoms, or a boroxine ring compound of formula (3): wherein R 4 has the same meaning as defined above, or a mixture thereof, in the presence of a nickel catalyst and a base.