Patents by Inventor Agnija Ievina

Agnija Ievina has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Regeneration of 2,2?-cyclopropylidene-bis (oxazolines)
    Patent number: 8846944
    Abstract: The present invention provides a method for regeneration of chiral 2,2?-cyclopropylidene-bis(oxazolines), such as (3&R,3?aR,8aS,8?aS)-2,2?-cyclopropylidenebis-[3a,8a]-dihydro-8H-indeno-[1,2-d]-oxazole and (45,4?5,5R,5?R)-2,2?-cyclopropylidenebis-4,5-diphenyldihydro-4,5-oxazole, used as a part of complex catalysts for e.g. stereoselective addition reactions, from the reaction mixtures, by selective sorption of 2,2?-cyclopropylidene-bis(oxazolines) on a sorbent, such as silica gel, isolation of the sorbent from reaction mixture, desorption of 2,2?-cyclopropylidene-bis(oxazolines) from the sorbent with suitable organic solvent and final recovery of 2,2?-cyclopropylidene-bis(oxazolines) from the organic solvent used for desorption process. Catalytic quality of recovered compounds does not differ from those in freshly prepared catalysts.
    Type: Grant
    Filed: November 30, 2009
    Date of Patent: September 30, 2014
    Assignee: Latvian Institute of Organic Synthesis
    Inventors: Ivars Kalvinsh, Antons Lebedevs, Aleksandrs Chernobrovijs, Grigory Veinberg, Maksims Vorona, Agnija Ievina