Method for preparing morphinan derivative having diaryl ether skeleton using novel copper catalyst

A method for preparing a morphinan derivative, the method comprising:

• reacting a compound represented by the following general formula (I):
• wherein R1 represents a hydrogen atom, a C1-10 alkyl group optionally having a substituent, a C3-6 cycloalkyl C1-6 alkyl group optionally having a substituent, an aralkyl group optionally having a substituent, a heteroarylalkyl group optionally having a substituent, a C3-6 cycloalkyl group optionally having a substituent, a C6-10 aryl group optionally having a substituent, a heteroaryl group optionally having a substituent, a C2-6 alkenyl group optionally having a substituent, or an amino protecting group,
• R2, R3, and R4 are the same or different and each represent a hydrogen atom or an substituent, or
• with respect to the moiety:
• of the general formula (I),
• R2 and R4 are bonded to each other to represent:
• wherein a double line consisting of a solid line and a broken line represents a single bond or a double bond,
• wherein, when the double line consisting of a solid line and a broken line between A and B is a single bond, then A and B are the same or different and each represent CR6R7, C═O, or NR8, wherein R6 and R7 are the same or different and each represent a hydrogen atom, —C(═O)—R9, or —CR10(OH)—R11, and R8 to R11 each represent a hydrogen atom or an arbitrary substituent, and
• when the double line consisting of a solid line and a broken line between A and B is a double bond, then A and B are the same or different and each represent CR6 or N, wherein R6 and R9 to R11 each represent the same as mentioned above, and
• when the double line consisting of a solid line and a broken line between D and D is a single bond, then D represents CH2, and when the double line consisting of a solid line and a broken line between D and D is a double bond, then D represents CH, or
• R2 to R4 are bonded to each other to represent:
• wherein X represents CH2, NR8 (R8 represents a hydrogen atom or an arbitrary substituent), or O, Y represents CH2 or C═O, and R12 represents an amino protecting group or an acyl group, and
• R5 represents a hydrogen atom, a hydroxy group, or —OR13 (R13 represents a hydroxy protecting group),
• with a compound represented by the following general formula (II):
• wherein R14 and R15 are the same or different and each represent a hydrogen atom or an arbitrary substituent, and Hal represents a halogen atom,
• in an organic solvent in the presence of a base, a monovalent copper compound, and a zero-valent metallic copper, wherein the monovalent copper compound is at least one selected from the group consisting of cuprous chloride, cuprous bromide, cuprous iodide and cuprous oxide, and the zero-valent metallic copper is copper powder, and
• the morphinan derivative being represented by the following general formula (III):
• wherein R1 to R5, R14, R15, and D each represent the same as mentioned above.