Preparation of 1,3-(substituted-diaryl)-1,2,4-triazoles and intermediates therefrom
View Patent ↗The invention in this document is related to the field of preparation of 1,3-(substituted-diaryl)-1,2,4-triazoles and certain intermediates derived therefrom, where said intermediates are useful in the preparation of certain pesticides disclosed in U.S. Pat. No. 8,178,658.
1. A process comprising:
reacting a compound of formula 1.2 with a (R 2 —OC(═O)-phenyl)boronic acid, (R 2 —OC(═O)-phenyl)boronic ester, or potassium (R 2 —OC(═O)-phenyl trifluoroborate salt, to produce a compound of formula 1.3
wherein
X is Cl, Br, or I,
R 1 is a (C 1 -C 6 ) haloalkoxy;
R 2 is H or (C 1 -C 6 ) alkyl; and
said reacting is conducted in the presence of a base, a palladium catalyst,
a polar aprotic solvent.
2. A process according to claim 1 wherein said base is potassium carbonate, sodium carbonate, sodium bicarbonate, potassium fluoride, or mixtures thereof.
3. A process according to claim 1 wherein said palladium catalyst is selected from bis(triphenylphosphine)palladium (II) chloride, tetrakis(triphenylphosphine)palladium (0), or mixtures thereof.
4. A process according to claim 1 wherein R 1 is trifluoromethoxy or pentafluoroethoxy.
5. A process according to claim 1 wherein R 2 is methyl or ethyl.
6. A process according to claim 1 wherein said solvent is acetonitrile, dioxane, dimethyoxyethane, tetrahydrofuran, or mixtures thereof.
7. A process according to claim 1 further comprising saponifying a compound of formula 1.3 to produce a compound of formula 1.4
wherein R 2 is(C 1 -C 6 ) alkyl.
8. A compound having the following structure
9. A compound having the following structure