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. 14, 1998
Filed:
Dec. 07, 1995
Robert B Wardle, Logan, UT (US);
W Wayne Edwards, Tremonton, UT (US);
Thiokol Corporation, Ogden, UT (US);
Abstract
A process for the hydrogenolysis of 2,4,6,8,10,12-hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo�5.5.0.0.sup.5,9.0 .sup.3,11 !dodecane ('HBIW') is disclosed. In the process, a quantity of HBIW, a cosolvent, and a bromine source are placed into a reaction vessel. Acetic anhydride and a palladium hydrogenolysis catalyst are rapidly added to the reaction vessel. The hydrogenolysis catalyst should be substantially free of water. The reaction vessel is purged of an atmosphere capable of reacting with hydrogen, and hydrogen is quickly introduced into the reaction vessel to convert the HBIW to tetraacetyldibenzylhexaazaisowurtzitane ('TADB'). The acetic anhydride is added immediately prior to hydrogen introduction so that the acetic anhydride does not have time to react with the HBIW to form an acetylated derivative prior to commencement of the desired hydrogenation reaction. The process requires very little palladium catalyst, preferably less than 10% wt/wt based on the HBIW substrate. The TADB, precipitated on the palladium hydrogenolysis catalyst, is subjected to a second hydrogenation step using a formic acid solvent in the presence of hydrogen to form tetraacetyldiformylhexaazaisowurtzitane ('TADF').