| titleOfInvention |
PROCEDURE FOR THE PREPARATION OF 2-CYANE INDOL DERIVATIVES ".," The present invention refers to a process for the preparation of 2-cyano indole derivatives, of the formula: (SEE FIGURE) where: R1 is hydrogen, halogen, alkoxy from C1 to C3 or nitro; R2 is hydrogen, halogen or C1 to C3 alkoxy, and R4 is hydrogen consisting of cyclizing a hydrazone derivative of the formula: (SEE FIGURE) where R1, R2, R3 and R4 are as defined above , with an acidic condensing agent. |