Preparation of 9,9-bis-(4-hydroxyphenyl)-fluorene

Number of patents in Portfolio can not be more than 2000

United States of America Patent

PATENT NO 5169990
SERIAL NO

07833769

Stats

ATTORNEY / AGENT: (SPONSORED)

Importance

Loading Importance Indicators... loading....

Abstract

See full text

In the production of 9,9-bis-(4-hydroxphenyl)-fluorene by condensation by fluorenone and phenol in a molar ratio of 1:4 to 1:8 at 30.degree. to 90.degree. C. in the presence of gaseous hydrogen chloride and .beta.-mercapto-propionic acid as catalyst, the improvement comprising mixing the completed reaction mixture with a polyalkylene glycol, distilling excess phenol from the mixture, and mixing the distillation residue with a solvent miscible with the polyalkylene glycol, recovering the crystallized product, suspending the crystallized product in water and heating the suspension to obtain highly pure 9,9-bis-(4-hydroxyphenyl)-fluorene as white crystals.

Loading the Abstract Image... loading....

First Claim

See full text

Family

Loading Family data... loading....

Patent Owner(s)

Patent OwnerAddress
RUTGERSWERKE AKTIENGESELLSCHAFTA CORPORATION OF GERMANY

International Classification(s)

  • [Classification Symbol]
  • [Patents Count]

Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Kleffner, Hans W Battenberg/Pfalz, DE 10 12
Orth, Winfried Hassloch/Pfalz, DE 24 52
Pastorek, Emmerich Hemsbach a.d. Bergstrasse, DE 8 11
Weiss, Wolfgang Neckarhausen, DE 29 209

Cited Art Landscape

Load Citation

Patent Citation Ranking

Forward Cite Landscape

Load Citation