PROCESSES FOR SYNTHESIS OF 2-AMINO-4,6-DIMETHOXYBENZAMIDE AND OTHER BENZAMIDE COMPOUNDS Russian patent published in 2018 - IPC C07C231/02 C07C231/06 C07C231/12 C07C233/25 C07C237/44 C07C255/59 C07C255/60 

FIELD: chemistry.

SUBSTANCE: invention relates to a process for the preparation of compound I. Method comprises steps (i) to (iii). Step (i) comprises combination of at least one compound II with at least one halogenating agent to produce at least one compound III. Step (ii) comprises combination of at least one compound III with at least one cyanating agent to produce at least one compound IV. Step (iii) comprises combination of at least one compound IV with at least one hydrating agent and / or a hydrating catalyst to produce at least one compound I. In formulae I-IV, R¹ and R⁵ are hydrogen, C₁-C₆ alkyl, hydroxy or C₁-C₆ alkoxy; R², R³ and R⁴ are hydrogen, C₁-C₆ alkyl or C₁-C₆ alkoxy; R⁶ and R⁷ are hydrogen, C₁-C₆ alkyl, protective or directing group; X is Cl, Br, I, triflate, tosylate or mesylate; and at least one of R¹ and R⁵ represents hydrogen. Where in compound II R⁷ represents a protecting or guiding group and or (1) before the start of step (ii) at least one compound III is combined with at least one agent for removing the protective group so that protective or guiding group R⁷ is replaced with hydrogen or C₁-C₆ alkyl, or (2) before the beginning of step (iii), at least one compound IV is combined with at least one agent for removing the protective group so that, protective or guiding group R⁷ is replaced with hydrogen or C₁-C₆ alkyl. Invention also relates to various embodiments of the method of producing Compound I, in particular 2-amino-4,6-dimethoxybenzamide. (I)

(II)

(III)

(IV)

EFFECT: disclosed method enables to prepare compounds I, suitable as intermediates for the synthesis of various therapeutic agents.

38 cl, 2 dwg, 13 ex