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:
May. 04, 1976
Filed:
Jun. 02, 1975
Applicant:
Inventors:
Cecil L Frye, Midland, MI (US);
David E Spielvogel, Midland, MI (US);
Assignee:
Dow Corning Corporation, Midland, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07F / ; C07F / ; C07F / ;
U.S. Cl.
CPC ...
2604 / ; 2604 / ;
Abstract
Stereoisomers of cycloorganosiloxanes are interconverted without siloxane bond redistribution by reacting the cyclic siloxane with anhydrous zinc chloride, zinc bromide, ferric chloride, aluminum chloride or aryl phosphonium chlorides in the presence of nitro compounds or aryl phosphate esters as solvents. A typical example is the conversion of 2,6-trans-diphenylhexamethylcyclotetrasiloxane to the 2,6-cis-isomer by heating in 2-nitropropane solvent in the presence of anhydrous zinc chloride.