1: With ethylenediamine diacetic acid in 1,4-dioxane T=90°C; tandem Knoevenagel-hetero-Diels-Alder reaction; 4 h; 2: With hydrogenchloride; silica gel in water; trifluoroacetic acid T=20°C;
Khan, Suroor Ahmad; Zuberi, Shario Sami; Shamsuddin, K. M.
Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1983 , vol. <B> 22, # 8 p. 818 - 819