	US 12,234,254 B2
	Methods for producing crystalline L-glufosinate ammonium monohydrate
Brian Michael Green, Lutherville, MD (US); Rachel Melissa Witek, New Market, MD (US); Nadejda Pavlova, Gaithersburg, MD (US); and Matthew Richard Oberholzer, Wilmington, DE (US)
Assigned to BASF SE, Ludwigshafen (DE)
Appl. No. 17/603,759
Filed by BASF SE, Ludwigshafen (DE)
PCT Filed Apr. 15, 2020, PCT No. PCT/US2020/028191 § 371(c)(1), (2) Date Oct. 14, 2021, PCT Pub. No. WO2020/214631, PCT Pub. Date Oct. 22, 2020.
Claims priority of provisional application 62/978,005, filed on Feb. 18, 2020.
Claims priority of provisional application 62/834,675, filed on Apr. 16, 2019.
Prior Publication US 2022/0177499 A1, Jun. 9, 2022
Int. Cl. C07F 9/30 (2006.01); C12N 9/06 (2006.01)

CPC C07F 9/301 (2013.01) [C12N 9/0024 (2013.01); C12Y 104/03003 (2013.01); C07B 2200/13 (2013.01)]

35 Claims

1. A method for preparing crystalline L-glufosinate ammonium monohydrate, the method comprising:

(i) forming a mixture comprising a L-glufosinate starting material and an aqueous solution,

wherein the glufosinate starting material comprises L-glufosinate ammonium and D-glufosinate ammonium, and

wherein the aqueous solution comprises water and a water-miscible organic solvent;

(ii) crystallizing L-glufosinate ammonium from the mixture of step (i) to form L-glufosinate ammonium monohydrate crystals; and

(iii) separating at least a portion of the L-glufosinate ammonium monohydrate crystals from the aqueous solution following step (ii);

thereby preparing the crystalline L-glufosinate ammonium monohydrate,

wherein the crystalline L-glufosinate ammonium monohydrate comprises L-glufosinate ammonium monohydrate Form B.