METHODS FOR PRODUCING CERTAIN 2-(PYRIDINE-3-YL)THIAZOLES Russian patent published in 2018 - IPC C07D417/04 C07D213/83 

FIELD: biochemistry.

SUBSTANCE: invention relates to a process for the preparation of 2-(pyridine-3-yl)thiazoles. Process involves (i) reacting compound (I) with compound (II) to produce compound (III), wherein said reaction is carried out in a polar protic solvent at ambient pressure, followed by (ii) cyclizing compound (III) using a dehydrating agent to produce compound (IV). Dehydrating agent is selected from the group consisting of POCl₃, H₂SO₄, SOCl₂, P₂O₅, polyphosphoric acid, p-toluene sulfonic acid, trifluoroacetic anhydride or a mixture thereof, and said cyclization is carried out at an ambient pressure and a temperature of from 60 °C to 120 °C, wherein (A) R¹ is H; (B) R₂ is (C₁-C₆) alkyl; (C) R₃ is H or (C₁-C₆) alkyl; and (D) R₄ is H, (C₁-C₆) alkyl or cyclopropyl. Method further involves halogenating said R₃ in compound (IV) to F, Cl, Br or I in a polar solvent at a temperature of from 0 °C to ambient temperature. (I) (II) (III) (IV).

EFFECT: technical result is a method for the preparation of 2-(pyridin-3-yl)thiazoles, intended as intermediates for the synthesis of pesticidal thiazole amides.

7 cl, 3 ex