Method for making a di(aminoaryl)fluorene compound

A method for making a di(aminoaryl)fluorene compound, consisting essentially of:

• (a) reacting a fluorenone compound according structure (1):
• with excess aminobenzene according to structure (II):
• wherein:
• each R1, R2, R3, R4, R12, and R13 is independently a group that is inert in the polymerization of epoxy compounds, and
• R11 is H or (C1-C6)alkyl,
• in the presence of an acid catalyst, in a liquid medium comprising ortho-dichlorobenzene and from which the di(aminoaryl)fluorene compound is crystallizable, to form a crude product mixture comprising the di(aminoaryl)fluorene compound, wherein the acid catalyst is soluble in the liquid medium and is selected from the group consisting of:
• (i) Lewis acids having an affinity for oxygen, and (ii) Brønsted acids,
• (b) crystallizing di(aminoaryl)fluorene compound from the crude product mixture,
• (c) separating the product mixture into crystallized di(aminoaryl)fluorene compound and a filtrate, and, optionally, recycling at least a portion of the filtrate to step (a),
• (d) washing, in one or more iterations, the di(aminoaryl)fluorene compound with aromatic or substituted aromatic solvent,
• (e) washing, in one or more iterations, the di(aminoaryl)fluorene compound produced in step (d) with water, a (C1-C4)alkanol, or a mixture thereof, and
• (f) drying the di(aminoaryl)fluorene compound produced in step (e).