US 12,441,692 B2
Process for preparation of triazole compound
Jignesh Amrutlal Desai, Mumbai (IN); and Digish Manubhai Panchal, Mumbai (IN)
Assigned to UPL LIMITED, Mumbai (IN)
Filed by UPL Limited, Mumbai (IN)
Filed on Mar. 8, 2023, as Appl. No. 18/180,367.
Claims priority of application No. 202221012818 (IN), filed on Mar. 9, 2022.
Prior Publication US 2023/0286926 A1, Sep. 14, 2023
Int. Cl. C07D 249/08 (2006.01); C07D 301/02 (2006.01); C07D 303/08 (2006.01)
CPC C07D 249/08 (2013.01) [C07D 301/02 (2013.01); C07D 303/08 (2013.01); C07B 2200/13 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A process for preparing high purity cyproconazole of formula (I),

OG Complex Work Unit Chemistry
the process, free of column chromatography, comprising:
a) reacting a ketone of formula (II) with a sulfonium salt in the presence of a base to obtain a compound of formula (III);

OG Complex Work Unit Chemistry
wherein the sulfonium salt is obtained by reacting dimethyl sulfide and dimethyl sulfate in the presence of water;
b) reacting the compound of formula (III) with 1,2,4-triazole or its alkali metal salt to obtain a crude cyproconazole; and
c) treating the crude cyproconazole with an aqueous alcohol to obtain the high purity cyproconazole.