Methyl 2-methylthioindole-3-carboxylate

The reaction of wasabi phytoalexin (109) with excess 15% aqueous NaSMe gives methyl 2-methylthioindole-3-carboxylate (184,70%) and 140 (20%). In this reaction, formation of 2-methylthioindole-3-carboxylic acid (185) is not observed under various reaction conditions. The fact indicates that once 140 is formed, it does not undergo nucleophilic substitution reaction. In addition, hydrolysis of the... 

C. Ethyl 2-methylindole-5-carboxylate. A solution of lO.Og. (0.040 mole) of ethyl 2-methyl-3-methylthioindole-5-carboxylate in 300 ml. of absolute ethanol is placed in a 500-ml., three-necked, round-bottomed flask fitted with a mechanical stirrer. An excess (15 teaspoons) (Note 11) of freshly washed W-2 Raney nickel (Note 12) is added, and the mixture is stirred for one hour. Stirring is then stopped, the liquid phase is decanted, and the catalyst is washed twice by stirring for 15 minutes with 100-ml. portions of absolute ethanol and decanting the solvent. The combined ethanolic solutions are concentrated on a rotary evaporator, and the residual solid is dissolved in 150 ml. of warm dichloromethane. This solution is dried over anhydrous magnesium sulfate and filtered, and the drying agent is washed with 40 ml. of dichloromethane. Concentration of the combined filtrates with a rotary evaporator gives... 

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