Process for preparation of intermediates
AssigneeUpl Ltd
InventorsSantosh Ganpat Shelke, Talati Paresh Vithaldas, Jaidev Rajnikant Shroff, Vikram Rajnikant Shroff
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Abstract
Disclosed herein is a process for preparation of 1-chloro-2-(1-chlorocyclopropyl)-3-(2-chlorophenyl)propan-2-ol (compound of formula (I)) and 2-(1-chlorocyclopropyl)-2-[(2-chlorophenyl)methyl]oxirane (compound of formula (II)), which are synthetic intermediates in the preparation of triazole fungicides. The process comprises reacting a Grignard reagent of 2-chlorobenzyl halide with 1-chloro-1-chloroacetylcyclopropane, wherein said reaction is carried out at temperatures between 0° C. and 100° C. and characterized in that said reaction is carried out in a solvent system comprising methyl tetrahydrofuran and toluene.
Claims3
A process for preparation of a mixture of 1-chloro-2-(1-chlorocyclopropyl)-3-(2-chlorophenyl)propan-2-ol of formula (I)
- and 2-(1-chlorocyclopropyl)-2-[(2-chlorophenyl)methyl]oxirane of formula (II)
- comprising reacting a Grignard reagent of 2-chlorobenzyl halide with 1-chloro-1-chloroacetylcyclopropane,
- wherein said reaction is carried out at temperatures between 0° C. and 40° C. and
- characterized in that said reaction is carried out in a solvent system comprising methyl tetrahydrofuran and toluene in a volume ratio of methyl tetrahydrofuran to toluene of 1:1.5 to 1:5, and
- further characterized that said mixture comprises 1-chloro-2-[2-(2-chlorophenyl)ethyl]benzene in an amount of 3 to 5% by weight.
A process for preparing prothioconazole comprising:
- (a) reacting a Grignard reagent of 2-chlorobenzyl halide with 1-chloro-1-chloroacetylcyclopropane in a solvent system comprising methyl tetrahydrofuran and toluene in a volume ratio of methyl tetrahydrofuran to toluene of 1:1.5 to 1:5 to form a mixture of 1-chloro-2-(1-chlorocyclopropyl)-3-(2-chlorophenyl)propan-2-ol and 2-(1-chlorocyclopropyl)-2-[(2-chlorophenyl)methyl]oxirane,
- wherein said reaction is carried out at temperatures between 0° C. and 40° C., and
- said mixture comprises 1-chloro-2-[2-(2-chlorophenyl)ethyl]benzene in an amount of 3 to 5% by weight;
- and
- preparing prothioconazole from the product of step (a).
A process for preparing prothioconazole comprising:
- (a) reacting a Grignard reagent of 2-chlorobenzyl halide with 1-chloro-1-chloroacetylcyclopropane in a solvent system comprising methyl tetrahydrofuran and toluene in a volume ratio of methyl tetrahydrofuran to toluene of 1:1.5 to 1:5 to form a mixture of 1-chloro-2-(1-chlorocyclopropyl)-3-(2-chlorophenyl)propan-2-ol and 2-(1-chlorocyclopropyl)-2-[(2-chlorophenyl)methyl]oxirane,
- wherein said reaction is carried out at temperatures between 0° C. and 40° C., and
- said mixture comprises 1-chloro-2-[2-(2-chlorophenyl)ethyl]benzene in an amount of 3 to 5% by weight;
- (b) reacting the step (a) product with 1,2,4-triazole to produce 2-(1-chlorocyclopropyl)-1-(2-chlorophenyl)-3-(1H-1,2,4-triazol-1-yl) propan-2-ol;
- and
- (c) reacting step (b) product with sulfur to produce prothioconazole.
Dependencies are inferred from the claim text.