Method for producing trimer of indole derivative, and trimer of indole derivative and laminated structure thereof

#The present invention relates to a method of producing indole derivative trimers as well as to novel indole derivative trimers obtainable by the method. The compositions containing any of the trimers as a main ingredient are applicable for various types of prevention of electrification, electrostatic shielding, capacitors, cells, EMI shielding agents, chemical sensors, display elements, organic EL materials, non-linear materials, antirust agents, adhesives, textiles, antistatic paints, electrodeposition painting, plating primers, conductive primers for electroostatic coating, electrolytic protection.

#As a method of chemically polymerizing indole, JP-A-5-148320 proposes a method including the step of dripping an indole solution into an oxidant solution. This method assumes only the case where indole containing no substituent is used as the raw material. There is no mention of an indole derivative containing a substituent. In addition, the product is a polymer containing indole as a repeating unit, and the publication does not include any description concerning formation of trimer.

#Synthesis of polymer by means of an electrolytic reaction of indole without any substituent, 4-nitroindole or 5-nitroindole is described in J. Electroanal. Chem., 414 (1996), p. 197 and synthesis of a trimer by means of an electrolytic reaction of indole without any substituent or 5-cyanindole is described in J. Chem. Soc., Faraday Trans., 93 (1997), p. 3791, respectively. When an oxidation and reduction testing (cycle testing) is performed using the unsubstituted or substituted indole produced by the method described in the documents, degradation of the trimer occurs, and as a result the cycle characteristics is rather poor, and the products can hardly be applied for production of conductive devices. Further, it is impossible to synthesize trimers on a large scale by the electrolytic reaction, and the method can hardly be employed as an industrial process.

#FIG. 1 is an IR chart showing indole-6-carbonitrile trimer according to Example 1;

#FIG. 2 is an IR chart showing indole-5-carbonitrile trimer according to Example 2;

#FIG. 3 is an IR chart showing 6-nitroindole trimer according to Example 3;

#The indole derivatives (a) of formula (1) used in the methods of the present invention include, for instance,

#indole; alkyl group-substituted indoles, such as 4-methyl indole, 5-methylindole, 6-methylindole, 7-methylindole, 4-ethylindole, 5-ethylindole, 6-ethylindole, 7-ethylindole, 4-n-propylindole, 5-n-propylindole, 6-n-propylindole, 7-n-propylindole, 4-iso-propylindole, 5-iso-propylindole, 6-iso-propylindole, 7-iso-propylindole, 4-n-butylindole, 5-n-butylindole, 6-n-butylindole, 7-n-butylindole, 4-sec-butylindole, 5-sec-butylindole, 6-sec-butylindole, 7-sec-butylindole, 4-t-butylindole, 5-t-butylindole, 6-t-butylindole, 7-t-butylindole; alkoxy group substituted indoles, such as 4-methoxyindole, 5-methoxyindole, 6-methoxyindole, 7-methoxyindole, 4-ethoxyindole, 5-ethoxyindole, 6-ethoxyindole, 7-ethoxyindole, 4-n-propoxyindole, 5-n-propoxyindole, 6-n-propoxyindole, 7-n-propoxyindole, 4-iso-propoxyindole, 5-iso-propoxyindole, 6-iso-propoxyindole, 7-iso-propoxyindole, 4-n-butoxyindole, 5-n-butoxyindole, 6-n-butoxyindole, 7-n-butoxyindole, 4-sec-butoxyindole, 5-sec-butoxyindole, 6-sec-butoxyindole, 7-sec-butoxyindole, 4-t-butoxyindole, 5-t-butoxyindole, 6-t-butoxyindole, 7-t-butoxyindole; acyl group-substituted indoles, such as 4-acetylindole, 5-acetylindole, 6-acetylindole, and 7-acetylindole; aldehyde group-substituted indoles, such as indole-4-carbaldehide, indole-5-carbaldehide, indole-6-carbaldehide, and indole-7-carbaldehide; carboxyl group-substituted indoles, such as indole-4-carboxylic acid, indole-5-carboxylic acid, indole-6-carboxylic acid, and indole-7-carboxylic acid; carboxylic ester group-substituted indoles, such as methyl indole-4-carboxylate, methyl indole-5-carboxylate, methyl indole-6-carboxylate, and methyl indole-7-carboxylate; sulfonic group-substituted indoles, such as indole-4-sulfonic acid, indole-5-sulfonic acid, indole-6-sulfonic acid, and indole-7-sulfonic acid; sulfonic ester group-substituted indoles, such as methyl indole-4-sulfonate, methyl indole-5-sulfonate, methyl indole-6-sulfonate, methyl indole-7-sulfonate; cyano group-substituted indoles, such as indole-4-carbonitrile, indole-5-carbonitrile, indole-6-carbonitrile, and indole-7-carbonitrile; hydroxy group-substituted indoles, such as 4-hydroxyindole, 5-hydroxyindole, 6-hydroxyindole, and 7-hydroxyindole; nitro group-substituted indoles, such as 4-nitroindole, 5-nitroindole, 6-nitroindole, 7-nitroindole; amino group-substituted indoles, such as 4-aminoindole, 5-aminoindole, 6-aminoindole, and 7-aminoindole; amide group-substituted indoles, such as 4-carbamoylindole, 5-carbamoylindole, 6-carbamoylindole, and 7-carbamoylindole; and halogen group-substituted indoles such as 4-fluoroindole, 5-fluoroindole, 6-fluoroindole, 7-fluoroindole, 4-chloroindole, 5-chloroindole, 6-chloroindole, 7-chloroindole, 4-bromoindole, 5-bromoindole, 6-bromoindole, 7-bromoindole, 4-iodoindole, 5-iodoindole, 6-iodoindole, and 7-iodoindole.

#Among these, the acyl group-substituted indoles, carboxylic group-substituted indoles, cyano group-substituted indoles, nitro group substituted indoles, fluoro group-substituted indoles are preferable in actual use.