METHODS FOR ENAMINE PRODUCTION Russian patent published in 2017 - IPC C07D295/84 C07C209/52 C07C323/27 

FIELD: chemistry.

SUBSTANCE: ccording to the method, enamines of general formula (I) and water are produced. The method comprises (A) first mixture interarion with the second mixture in the reaction zone, (1) where the said first mixture comprises amine of the formula , where R4 and R5, taken together with N, constitute a 5- or 6-member substituted or unsubstituted ring, and (2) where the said second mixture comprises a non-polar solvent with a high boiling point and carbonyl selected from aldehyde or ketone of the following formula: , wherein (a) one of R1 and R2 is a radical independently selected from C_1-C₈ alkyl, and the other is S-R6, where R6 is independently selected from C_1-C₈ alkyl, and (b) R3 is selected from H and C_1-C₈ alkyl. The said amine is added to the lower layers of the reaction mixture, (B) interaction of the said amine and the carbonyl in the said reaction zone to obtain enamine and H₂O under azeotropic distillation, comprising (1) pressure of about 1000 pascals (Pa) to about 60,000 Pa and (2) temperature below the thermal decomposition temperature of the said enamine during this interaction; and (C) vapor phase removal the from the said reaction zone, wherein the said steam phase contains the said non-polar solvent with a high boiling point and H₂O, wherein the weight ratio of (quantity of the first mixture, added to the said reaction area):(quantity of vapor removed from the said reaction zone) is from about (1 part of the added first mixture):(1 part of removed vapor) to (1 part of the added first mixture):(20 parts of removed vapor). Pyrrolidine is advantageously used as amine, 3-methylsulfanyl-butyraldehyde and toluene are used as carbonyl and nonpolar solvent to obtain 2-(3-metilsulfanilbut-1-enyl) pyrrolidine as the desired product.

EFFECT: method allows to obtain products with a high yield, eliminate application of dryers, as well as allows for the process without using temperature conditions conducive to thermal decomposition of the resulting enamines.

15 cl, 4 ex