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:
Dec. 19, 2000
Filed:
Mar. 30, 1998
Applicant:
Inventors:
Assignee:
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C07F / ; C07F / ; C07F / ;
U.S. Cl.
CPC ...
556 87 ; 556431 ; 556466 ; 556467 ; 585360 ; 526160 ; 526943 ; 502103 ; 502117 ;
Abstract
A process for preparing bis-cyclopentadienyl compounds bridged by a methylene group is reported, said process comprising reacting formaldehyde with a cyclopentadienyl compound in the presence of a base and of a solvent having a dielectric constant (.epsilon.), measured at 25.degree. C., higher than 7. The bridged compounds, obtainable in high yields with this simple single-step process, can be used to prepare ansa-metallocenes, active as catalyst components in the polymerization of olefins.