反应详情

Nineteen (19) grams of the 3,6-diacetyl-N-ethylcarbazole from Example 1 was dissolved in 800 ml pyridine and added to 400 ml of 5% aqueous sodium hydroxide in a 6-liter Erlenmeyer flask. While cooling the mixture in ice, 1429 ml of 5% sodium hypochlorite (bleach) was added. The reaction was allowed to stir 3.5 hours at room temperature. A concentrated solution of sodium bisulfite was added until no hypochlorite remained (starch-iodine test). The basic solution was neutralized with concentrated HCl and the precipitated diacid filtered. The yield of N-ethylcarbazole-3,6-dicarboxylic acid was 13.12 g. Elemental analysis was as follows. Calculated for C16H13NO4 :%C, 67.84; %H, 4.63; %N, 4.94. Found: %C, 67.60; %H, 4.64; %N, 4.88.

1. temperatureWhile cooling the mixture in ice
2. filtrationthe precipitated diacid filtered