Reaction of propylamine with 2,3-estrone o-quinone (2,3-EQ) and 3,4-estrone o-quinone (3,4-EQ) gave a complex mixture of mostly unidentifiable products. Several reaction products were isolated and identified using spectroscopic techniques. With 3,4-EQ, both 1,2- and 1,6-Michael addition reactions were observed in which 4-hydroxyestradiol, an estrogen oxazole, and a violet compound identified as the iminoquinone adduct that was obtained by condensation of one molecule of an estrogen o-aminophenol with the 1,6-Michael addition product of propylamine to 3,4-EQ were identified. Unlike reactions of 3,4-EQ, only 1,2-Michael addition reactions were observed with 2,3-EQ leading to the formation of 2-hydroxyestradiol, two monoiminoquinone compounds, and a bisiminoquinone product.