Method for producing amide compound

A method for producing an amide compound, comprising a step of forming an amide bond between a carboxyl group on the right side of general formula (1) of a compound represented by general formula (1) and an amino group on the left side of general formula (2) of a compound represented by general formula (2) in the presence of a Lewis acid catalyst and a silylating agent to synthesize a compound represented by general formula (3),

• wherein, in general formulas (1), (2), and (3),
• R1, R2, R4, and R5 each independently represent a hydrogen atom, halogen atom, hydroxy group, carboxyl group, nitro group, cyano group, or thiol group, or a monovalent hydrocarbon group or heterocyclic group, which may have one, two, or more substituents, where the monovalent hydrocarbon group or heterocyclic group may be bonded to a nitrogen atom via a linker group;
• R3 and R6 each independently represent a hydrogen atom, carboxyl group, or hydroxy group, or a monovalent hydrocarbon group or heterocyclic group, which may have one, two, or more substituents, where the monovalent hydrocarbon group or heterocyclic group may be bonded to a carbon atom via a linker group;
• R1 and R3 may be bonded together to form, together with a carbon atom to which R1 bonds and a nitrogen atom to which R3 bonds, a heterocycle which may have one, two, or more substituents, or R4 and R6 may be bonded together to form, together with a carbon atom to which R4 bonds and a nitrogen atom to which R6 bonds, a heterocycle which may have one, two, or more substituents;
• A1 to A4 each independently represent a divalent aliphatic hydrocarbon group having 1 to 3 carbon atoms, which may have one, two, or more substituents;
• p1 to p4 each independently represent 0 or 1;
• m and n are each independently an integer of 1 or higher and represent the number of constitutional units represented by a structure in [ ];
• PG1 represents a protecting group of an amino group;
• PG2 represents a protecting group of a carboxyl group;
• and
• an amino group on the left side of general formula (2) may form a salt with an acid,
• wherein the Lewis acid catalyst is a metal catalyst,
• the metal catalyst is a compound containing one or more metals selected from the group consisting of titanium, zirconium, hafnium, tantalum, and niobium, and
• the silylating agent is one or more compounds selected from the group consisting of silylimidazole compounds, silyltriazole compounds, silylhalide compounds, silylamide compounds, and silylamine compounds.