Acetic Anhydride → 7-(1-Ethyl-2-methylindol-3-yl)-7-(1,2-diphenylindolizin-3-yl)-5,7-dihydrofuro[3,4-b]pyridin-5-one

Participants

Reaction Steps

A mixture of 1.6 grams of (1-ethyl-2-methylindol-3-yl) (3-carboxy-pyridin-2-yl)ketone, 1.85 grams of 1,2-diphenylindolizine and 10 ml. of acetic anhydride was heated at about 40° C. for 104 minutes and then cooled in an ice bath. The reaction mixture was filtered and the product was repeatedly recrystallized from a toluene-petroleum ether mixture until a constant melting point of 206.5°-207.5° C. was obtained. A chloroform solution of the final product produced a blue color when applied to a record sheet material coated with a zinc-modified phenolic resin.

Provenance & Evidence