p-Toluenesulfonic acid → 2-(1-pentyl-1H-pyrrol-2-yl)-[1,4]-naphthoquinone

Participants

Reaction Steps

6.32 millimol of 1,4-naphthoquinone and 3.16 millimol of N-pentylpyrrole were stirred in 50 ml of chloroform in a round-bottomed flask for 5 hours at room temperature, the reaction being catalysed by addition of a few milligrams of para-toluenesulphonic acid. The reaction medium was diluted with 50 ml of chloroform and then washed four times with 50 ml of water and finally with saturated aqueous NaCl solution. The resulting organic phase was dried over Na2SO4 and then concentrated under vacuum. The product 2-(1-pentyl-1H-pyrrol-2-yl)-[1,4]-naphthoquinone was thus isolated, in the form of an oil, in a yield of 26% after purification by chromatography on a column of silica.

Provenance & Evidence