Synthesis of vicinal difluoro aromatics and intermediates thereof

Aromatic compounds, especially naphthalene derivatives, bearing fluorine atoms on adjacent carbons (i.e., vicinal) have been found to be useful as liquid crystal materials. They are typically made by a multi-step process, starting from the aromatic amine via a fluoro-dediazoniation process (N. Yoneda and T. Fukuhara, , vol. 52, No. 1 (1996), pages 23-36). A method of preparing vicinal difluoro aromatic compounds in high yield from hydroxy aromatic compounds and a method of preparing intermediates thereof. The hydroxy aromatic compound can be a mono-, bi- or tricyclic aromatic in which the rings are separate or fused. One or more of the rings can contain heteroatoms, such as oxygen, nitrogen, or sulfur, and can contain one or more substitutions, in addition to the hydroxy substitution.