Levulinic Acid → Indole

Participants

Reaction Steps

Condensation of hydrazine hydrochloride (2) with levulinic acid (3) in acetic acid results in the formation of two regioisomeric indole derivatives 4 and 5 in a 1:7 ratio. The major regioisomer 5 can be isolated in pure form by crystallization of the reaction mixture. Alternatively, the indole mixture can be esterified with an alcohol such as 2-trimethylsilylethanol to afford the corresponding esters that can then be separated by a number of means, for example by chromatography.

Provenance & Evidence