The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 19, 1994
Filed:
Apr. 13, 1993
Robert G Bowman, Midland, MI (US);
Muthiah N Inbasekaran, Midland, MI (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
A process for the preparation of bishydroxy aromatic compounds, such as 9,9-bis(4-hydroxyphenyl)fluorene, involving contacting a ketone, such as fluorenone, with phenol or substituted phenol in the presence of a mercaptan cocatalyst and a solid superacid catalyst of Hammett acid strength H.sub.0 greater than about -13.0. Solid superacid catalysts include the sulfates, sulfated oxides, sulfated oxyhydroxides, and sulfated oxysilicates of aluminum, tin, and the Group IVA metals, such as zirconium, as well as mixed metal oxides, such as tungsten-zirconium oxides. Isolated yields are high for 9,9-bis(4-hydroxyphenyl)fluorene.