A facile, choline chloride/urea catalyzed solid phase synthesis of coumarins via Knoevenagel condensation was written by Harishkumar, Hosanagara N.;Mahadevan, Kittappa M.;Kiran Kumar, Hittalumane C.;Satyanarayan, Nayak D.. And the article was included in Organic Communications in 2011.Related Products of 51473-74-6 This article mentions the following:
The influence of choline chloride/urea ionic liquid in solid phase on the Knoevenagel condensation is demonstrated. The active methylene compounds such as meldrum acid, diethylmalonate, Et cyanoacetate, dimethylmalonate, were efficiently condensed with various salicylaldehydes in presence of choline chloride/urea ionic liquid without using any solvents or addnl. catalyst. The reaction is remarkably facile because of the air and water stability of the catalyst, and needs no special precautions. The reactions were completed within 1 h with excellent yields (95%). The products formed were sufficiently pure, and can be easily recovered. The use of ionic liquid choline chloride/urea in solid phase offered several significant advantages such as low cost, greater selectivity and easy isolation of products. In the experiment, the researchers used many compounds, for example, 7-(Diethylamino)-2-oxo-2H-chromene-3-carbonitrile (cas: 51473-74-6Related Products of 51473-74-6).
7-(Diethylamino)-2-oxo-2H-chromene-3-carbonitrile (cas: 51473-74-6) belongs to nitriles. The R-C-N bond angle in and nitrile is 180° which give a nitrile functional group a linear shape. Both the carbon and the nitrogen are sp hydridized which leaves them both with two p orbitals which overlap to form the two π bond in the triple bond. Alkyl nitriles are sufficiently acidic to undergo deprotonation of the C-H bond adjacent to the CN group.Strong bases are required, such as lithium diisopropylamide and butyl lithium. The product is referred to as a nitrile anion. Related Products of 51473-74-6
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts