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:
Nov. 30, 1976
Filed:
Jun. 02, 1975
Robert P Allen, Longview, TX (US);
Hugh J Hagemeyer, Jr, Longview, TX (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
The present invention relates to a process for the manufacture of 2,2-disubstituted propiolactones via the pyrolysis of methylene diisoalkylate in the vapor phase over a fixed bed catalyst system. The reaction of the invention is as follows: ##SPC1## Wherein R is alkyl of from 1 to 4 carbon atoms and R.sup.1 is alkyl of from 1 to 4 carbon atoms or phenyl. The catalyst comprises an oxide of a metal selected from the group Ag, U, Zn, Ti, Zr, Th, Ta, Nb, Mo, W, and Sn on a suitable support. A preferred catalyst is the metal oxide-silica gel complex which results from heating the calcined residue of a salt of a metal selected from the group consisting of Ta, Ti, Nb and Zr supported upon a silica gel in the presence of nitrogen and steam at a temperature of from about 650.degree. C. to about 1000.degree. C. The process is operable at temperatures from about 240.degree. C. to about 360.degree. C. with contact times ranging from about 0.1 second to about 30.0 seconds. The gaseous ester feed may, if desired, be diluted with an inert gas such as nitrogen and the reactor may be run at atmospheric, or superatmospheric pressure.