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. 21, 1992
Filed:
Nov. 20, 1989
Dennis J Malfer, Crestwood, MO (US);
John G Bostick, Belleville, IL (US);
Lawrence J Cunningham, Kirkwood, MO (US);
J Vincent Hanlon, St. Louis, MO (US);
Ethyl Petroleum Additives, Inc., St. Louis, MO (US);
Abstract
When a phenol having substituents in at least the 2- and 4-positions but having a hydrogen atom in the 6-position, or a phenol having substituents in at least the 2- and 6-positions but having a hydrogen atom in the 4-position is reacted with formaldehyde and 1,3-propanediamine, a unique insertion-condensation reaction occurs whereby the product is a hexahydropyrimidine derivative which may be represented by the general formula ##STR1## wherein R.sub.1 is (i) a 2-hydroxybenzyl group having an inert substituent (preferably a hydrocarbyl substituent) in at least the 3- and 5-positions or (ii) a 4-hydroxybenzyl group having an inert substituent (preferably a hydrocarbyl substituent) in at least the 3- and 5-positions; and R.sub.2 is (i) a 2-hydroxybenzyl group having an inert substituent (preferably a hydrocarbyl substituent) in at least the 3- and 5-positions or (ii) a 4-hydroxybenzyl group having an inert substituent (preferably a hydrocarbyl substituent) in at least the 3- and 5-positions or (iii) a hydrogen atom. Uses for such compounds include their use as antioxidants and stabilizers for various substrates, such as fuels, lubricants, and functional fluids.