Patent ID: 8729284

Claim:
A method for producing an anionized meso-form double-cross-linked ligand represented by formula (3): the method comprising: contacting a compound represented by formula (1) with a compound represented by formula (2) at −25° C. or less, to form a reaction mixture: and introducing an anionizing agent into the reaction mixture within 5 hours after the contacting, wherein: R 1 to R 10 independently represent a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing group or a hetero-atom-containing group; A and A′ independently represent a cross-linking group comprising an atom belonging to the 14 th group of the periodic table; M and M′ independently represent an atom belonging to the 1 st or the 2 nd group of the periodic table; n represents 2 when M or M′ is an atom belonging to the 1 st group of the periodic table, and represents 1 when M or M′ is an atom belonging to the 2 nd group of the periodic table; and X represents a halogen atom.